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AWS RDS parameter group max_allowed_packet - How to Modify the parameter ?


This article covers how to create and modify the AWS RDS parameter. 


What is max_connect_errors parameter ?

This parameter indicates how many connection errors are possible before the server blocks a host. If more than max_connect_errors successive connection requests from a host are interrupted without a successful connection, the server blocks that host from further connections. The default value is 100 and can be tuned to your security requirements and environment.

For example, if max_connect_errors=5000, after 5,000 connection requests from Host X are interrupted you get an error like the following:

Host X is blocked because of many connection errors ()

You can simply Unblock the host using the following command:

mysql> flush hosts;
mysql> show global variables like 'max_connect_errors';

+| Variable_name      | Value |
+--------------------+-------+
| max_connect_errors | 5000|
+--------------------+-------+

1 row in set (0.00 sec)

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PostgreSQL backup failed in Web help desk - Fix it Now ?


This article covers methods to resolve PostgreSQL database and fix PostgreSQL error. It may be necessary to create a backup and restore your Web Help Desk database.

This is how to back up and restore the Web Help Desk 12.x PostgreSQL embedded database. The process involves creating a backup from the web interface and restore using the embedded pgAdmin application on the Web Help Desk.

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AWS S3 403 Forbidden Error - Fix it Now ?


This article covers methods to fix HTTP 403 Forbidden error for our customers. 

To troubleshoot the HTTP 403 Forbidden error from the Amazon S3 console, check the following:

  • Missing permissions to s3:PutObject or s3:PutObjectAcl.
  • Missing permissions to use an AWS Key Management Service (AWS KMS) key.
  • Explicit deny statement in the bucket policy.
  • Bucket access control list (ACL) doesn't allow the AWS account root user to write objects.
  • AWS Organizations service control policy doesn't allow access to Amazon S3.

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Error: "backup doesn't exist" in VestaCP - Fix it Now ?


This article covers methods to resolve Error: "backup doesn't exist" in VestaCP which generally happens while migrating a user to a new server.

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"SR BACKEND FAILURE 181" error - Fix it Now ?


This article covers how to fix "SR BACKEND FAILURE 181" error. Generally, user experiences issues with any storage related operations after installation or upgrade to XenServer 6.x. 

As a workaround, you can remove all special characters from the virtual machine name-label and description fields.  Contact our Technical Support to assist you in resolving the issue. 

Note: Special character should not be used for the storage repository and description field.

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SolusVM html5 and vnc consoles not working - Fix it Now ?


This article covers how to fix "Server disconnected (code:1006)". Basically, this error happens as a result of misconfiguration in the noVNC feature or when SSL settings required for NoVNC to work are not configured.

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Windows server 2016 vss error 12347 - Fix it Now ?


This article covers methods to resolve Windows server 2016 vss error 12347. Basically, 'Windows server 2016 vss error 12347' occurs when the Backup of Shadow Copy Component Fails. This usually happens when the registry Volume Shadow Copy Service (VSS) writer did not respond to a query from the VSS service.

To resolve this Windows error, simply Reboot the Server where the problem exists.

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Smartermail 601 error - Ways to fix it ?


This article covers methods to fix the Smartermail 601 error. This can arise as a result to DNS lookup failure. You can try to contact your ISP and ask them to active PTR record on your ip and domain name.

Also, you can try the following fix:

  • check your domain or IP to be unblocked by spam checking website, the powerful website in this range is Barracuda'.
  • Try to test SMTP OUT by Telnet command by type: telnet IP port ( mostly 25 or 2525).
  • Get details about your PTR on the main domain you defined on Smartermail or etc mail server software.
  • Contact to your ISP to check to open the specific port 25).

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Create New Destinations for JetBackup


This article covers how to create New Destinations for JetBackup. Basically, clients choose to store at least one copy of backups locally and additional copies in at least one or more remote destinations. Remote destinations are usually slower than local destinations to backup and restore from due to bandwidth requirements. With this in consideration, many clients choose to store at least one copy of backups locally and additional copies in at least one or more remote destinations.

Whatever backup destination option(s) you choose, please make sure that your destination path is secure and has the appropriate privileges.


How To Secure Local Backup Storage ?

Prior to adding a destination to JetBackup, we advise securing the backup directory, so that only the allowed users can access that folder.

In order to do that, please connect to the destination via console/GUI, and make the directory in which you want to store your backups.

For example:

$ mkdir [-p] /mnt/backup_vol/jetbackup

Then we advise securing that destination so only one user can access it's content (except root):

$ useradd <jetbackup>
$ chown jetbackup:jetbackup /mnt/backup_vol/jetbackup
$ chmod 700 /mnt/backup_vol/jetbackup

Right now only two users that can access this directory are root and jetbackup.

Please search online, how to secure a backup folder for your particular file system (EXT, NTFS, FAT, etc..) on your system (Windows, Linux, macOS, BSD, etc..)

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Monitor MongoDB with Nagios XI - How to perform this ?


This article covers  how to monitor a MongoDB server with Nagios XI using the MongoDB Server Configuration Wizard in order to monitor the health of your server. The

wizard supplies checks to monitor the following: number of queries per second, memory usage, the number of databases on the server, and percentage of free connections available.


To Connect to MongoDB with the appropriate privileges:

Connect to mongod or mongos with the privileges specified in the Prerequisites section.

The following procedure uses the myUserAdmin created in Enable Access Control:

mongo --port 27017 -u myUserAdmin -p 'abc123' --authenticationDatabase 'admin'

The myUserAdmin has privileges to create roles in the admin as well as other databases.


To Modify Access for an Existing User in MongoDB:

  • You must have the grantRole action on a database to grant a role on that database.
  • You must have the revokeRole action on a database to revoke a role on that database.
  • To view a role's information, you must be either explicitly granted the role or must have the viewRole action on the role's database.

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Monitor Website Defacement With Nagios XI - How to do it ?


This article covers how to Monitor Website Defacement With Nagios. Basically, Nagios XI can monitor for potential Website defacement using the Website Defacement monitoring wizard. 


Benefits of Website Defacement Detection:

  • Fast detection of security breaches.
  • Fast detection of outages and website hijacking.
  • Increased website and web application availability.
  • Capacity planning information for future web server and application upgrades.

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Service Not Listed in WMI Wizard in Nagios - Fix it Now ?


This article covers methods to tackle Service Not Listed in WMI Wizard in Nagios. Basically, Service may not get listed in WMI Wizard in Nagios due to reasons like lower value of Truncate Output Length or insufficient permission of the user account. Windows Management Instrumentation (WMI) is a part of Windows operating systems and can provide management data and operational information about those system. WMI can be used to automate administrative tasks on remote Windows-based computers. Nagios Core and Nagios XI are capable of monitoring Windows machines via WMI. .


To Check the permissions of the files, use this command:

ls -ls /tmp/*.state

Here you can see that the root user/group is the owner of the file:

-rw-r--r-- 1 root root 91 Apr 24 16:10 /tmp/cwpss_checkcpu__1025143___.state

The simplest option is to delete the files with this command:

rm -rf /tmp/*.state

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SQL Server Error 19471: Create failed for Availability Group Listener


This article covers methods to fix SQL Server Error 19471. Basically,  "SQL Server Error 19471" can happen while configuring Always On Availability Group again on the database server.


To fix SQL Server Error 19471:

  • Create a Client Access Point (CAP) for the AOAG listener in Failover Cluster Manager.
  • Bring CAP Online.
  • Repair the CAP, if it is not coming ONLINE.
  • Once CAP comes online, remove it from failover cluster manager.
  • Add listener to AOAG in SSMS.

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WMI Monitoring With Nagios - How to do it ?


This article covers how to monitor Windows machines with Nagios XI using WMI.

Basically, to set up WMI monitoring with Nagios, we need to configure A WMI User Account On The Windows Machine and then set up the WMI permissions. Windows Management Instrumentation (WMI) is a technology that allows for agentless monitoring of Windows servers and workstations.


Benefits of WMI Monitoring With Nagios:

  • Increased server, services, and application availability.
  • Fast detection of server and operating system failures.
  • Fast detection of service and application failures.
  • Agentless monitoring.

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Install Python 3.9 on Debian 10 - Step by Step Process ?


This article covers Python installation on Debian Linux System. Basically, Python is a programming and scripting language developed under open source license, making it freely usable and distributable, even for commercial use. 

Python 3.9 is the latest major release of the Python language. It includes many new features such as new dict operators, new str functions, support for IANA time zone, and more.


After Python 3.9 installation on your Linux System, you can verify it easily by running the command:

python3.9 --version

The output should show the Python version installed.

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Install Proxmox VE 6 on Debian Buster (Debian 10) - Step by Step Process ?


This article covers the installation of Proxmox VE 6 server on Debian 10 (Buster) Linux system. Please note that you need a 64-bit processor with support for the Intel 64 or AMD64 CPU extensions.

Visit Proxmox Documentation website  for advanced configurations and to master Proxmox VE Administration.


To Access Proxmox VE web interface:

1. Connect to the Proxmox VE admin web interface on (https://youripaddress:8006).

2. Select "PAM Authentication" and authenticate with server's root user password.

3. And add your first network interface to it.

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Install the Acronis BackUp Plugin on cPanel - Step by Step Process ?


This article covers method to install the Acronis BackUp Plugin on cPanel.


To install the Acronis Backup plugin for WHM and cPanel, run the following command:

sh <(curl -L https://download.acronis.com/ci/cpanel/stable/install_acronis_cpanel.sh || wget -O -https://download.acronis.com/ci/cpanel/stable/install_acronis_cpanel.sh)

This command runs the installation script.


How to Install the backup agent ?

To back up the Virtuozzo container, the backup agent must be installed on its host as described in the Installing the backup agent on Virtuozzo host section.

1.Log into WHM UI.

2.Click Plugins> AcronisBackup.

3. Specify the credentials of the account to which the machine should be assigned. Make sure that you specify the credentials of an account created within the customer group (Customer administrator, Unit administrator, or User). Do not specify partner administrator credentials.

4. Follow the installation wizard. During the installation, the software checks if the ports required for communication with the cloud are open. 

If some of the ports are closed, the software shows numbers of these ports and the hostnames for which a port should be open. 

Open the ports, close the wizard, and restart the installation. 

Completing the installation may take several minutes. You can leave the page during this process. 

The backup agent can also be installed by using the command line.


To uninstall the Acronis Backup plugin for WHM and cPanel, run the following command:

$ yum remove acronis-backup-cpanel

Removing the extension will also uninstall the backup agent from the cPanel server.

The backup accounts you created and the backed-up data will be left intact.

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Exclude Files from Backups in DirectAdmin - How to do it ?


This article covers how to Exclude Files from Backups in DirectAdmin. 


User ability to skip paths from their tar.gz backup files in DirectAdmin.

i. New optional file:

/home/username/.backup_exclude_paths

where User can add paths to this file that they wish to have skipped from their backup.

The format of the file must be relative to /home/user and should not include a "/home/user" prefix.

2. New default internal directadmin.conf setting:

allow_backup_exclude_path=1

can be disabled by setting it to 0 and restarting DA.

A sample line in the .backup_exclude_paths would look like:

domains/domain.com/awstats

so that the path:

/home/username/domains/domain.com/awstats

is skipped from the backup.

This will add:

--exclude-from=/home/username/.backup_exclude_paths

Just after the -C /home/username option in the creation of BOTH the home.tar.gz and the user's backup tar.gz.

So using the feature will truly exclude the path, regardless of if it's in /home/user/domains, or /home/user/*.

As you may have noticed, the option uses tar's exclude-file option.

This supports patterns, eg:

*.gz

So you have skip those types of files, regardless of what path they're under.

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Monitoring Linux Using NCPA


This article covers how to go about setting up monitoring in Linux using NCPA. You will learn how to configure NCPA to monitor Linux.

NCPA is a cross-platform monitoring agent for Nagios Core and Nagios XI that runs on Windows, Linux/Unix, and Mac OS/X machines. Its features include both active and passive checks, remote management, and a local monitoring interface.


In Nagios XI wizards can be used to to perform configuration of hosts and services through the Web UI. Wizards take the complicated matter of creating hosts and services, defining configuration parameters, assigning contacts, contact groups, hostgroups, servicegroups, etc, into a easy steps form in the Nagios XI UI. 

Wizards can also be easily added to Nagios XI through the Admin -> Manage Wizards menu to expand the capabilities of Nagios XI.

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WHM Internal server error 500 - Fix it Now ?


This article covers different ways to troubleshoot and resolve WHM / cPanel Internal server error 500.

Basically, the "Internal server error 500" message happens while accessing WHM panel or cPanel and one of the cPanel process failing to load or still running in the background.


Other causes of 500 Internal Server Error in WHM?

  • Incorrect permissions settings, usually due to having a file as "world" writeable.
  • Incorrect permissions settings for use by another script (this is common with manual installs of forums or blogs).
  • Incorrect coding in the .htaccess file.

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Package conflict errors with ea-nginx on CloudLinux - Fix it Now ?


This article covers how to resolve Package conflict errors with ea-nginx on CloudLinux. Basically, Cloudlinux servers with ea-nginx, yum or cPanel updates tend to fall with this error. 


On Cloudlinux servers where already packages for ModSecurity2 are installed (ea-modsec-sdbm-util & ea-apache24-mod_security2), trying to install ea-nginx or run a yum update/cPanel update fails because as a part of ea-nginx dependencies, some of ModSecurity3 packages (ea-modsec30 & ea-modsec30-connector-nginx) will also be attempted to be installed, and that causes a conflict between the packages belonging to ModSecuirty2 and Modsecurity3, which in turn causes yum and UPCP to fail. 


To resolve systems that are currently experiencing this error, update EA packages to the beta branch:

$ yum update ea-* --enablerepo=cl-ea4-testing

 

To install ea-nginx on affected systems using the beta repository, install it with the following command:

$ yum install ea-nginx --enablerepo=cl-ea4-testing

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Database import hangs in Plesk - Fix it Now ?


This article covers methods to resolve Database importing hangs in Plesk with error reading communication packets. Generally, the database import task in Plesk fails due to non-optimized client databases.

The solution to this Plesk error is to simply optimize the databases.

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Configure filters in Nagios log server - Do it Now ?


This article covers method to customize Nagios Log Server Filters. Basically, to configure filters in Nagios log server, one needs to be familiar with the Filter Configuration options available within the log server.

Filters can be applied to messages before they are sent to Elasticsearch for indexing. They perform actions such as breaking apart messages into fields for easy searching, adding geo location information, resolving IP to DNS names and dropping messages you do not want indexed.

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Manage Clusters In Nagios Log Server - Fix it Now ?


This article covers how to manage and identify key information on your Nagios Log. Nagios Log Server is a clustered application, it consists of one or more instances of Nagios Log Server. An instance is an installation of Nagios Log Server, it participates in the cluster and acts as a location for the received log data to reside. The log data is spread across the instances using the Elasticsearch database, a special database used by Nagios Log Server.

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Configure SSL / TLS in Nagios Log Server - How to do it ?


This article covers how to configure SSL/TLS in Nagios Log Server. SSL/TLS provides security between the end user's web browser and Nagios Log

Server by encrypting the traffic. This guide is intended for use by Nagios Log Server Administrators who require encrypted connections to their Nagios Log Server.

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Alerting On Log Events With Nagios Log Server


This article covers Alerting On Log Events With Nagios Log Server. Basically, for alerting on Log Events with Nagios Log Server one needs to be familiar with the options available.

With this guide, you will learn how to create various alerts in Nagios Log Server, such as sending

them to a Nagios XI or Nagios Core monitoring server using Nagios Remote Data Processor

(NRDP), sending an email, sending SNMP traps and executing scripts.

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Analyzing Logs With Nagios Log Server


This article covers how to analyze  logs with Nagios Log Server.  Basically, in order to analyze logs with Nagios Log Server one needs to be familiar with the options in the Dashboards menu. This guide is very essential to Nagios Log Server administrators and users looking for information on querying, filtering and drilling down the data in Nagios Log Server.

You can audit your IT infrastructure, maintain historical records of usage of IT infrastructure, create reports, and analyze logs using the Nagios Log Server.

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Send test SNMP trap in Nagios - How does this work ?


This article covers how to send a trap to Nagios server to test SNMP Trap functionality.

Basically, when troubleshooting an SNMP Trap issue, it can be very helpful to remove the actual device that could be causing problems and use the snmptrap command instead.

So in this guide, you will learn all the methods of sending a trap to your Nagios server to test SNMP Trap functionality.


SNMP Trap Definition

The following trap definition can be placed in /etc/snmp/snmptt.conf which will allow the test traps sent above to be passed through to Nagios:

EVENT netSnmpExampleHeartbeatRate .1.3.6.1.4.1.8072.2.3.0.1 "netSnmpExampleHeartbeatRate" Normal
FORMAT SNMP netSnmpExampleHeartbeatRate
EXEC /usr/local/bin/snmptraphandling.py "$r" "SNMP Traps" "$s" "$@" "" "netSnmpExampleHeartbeatRate"


The default SNMP Trap configuration is stored in the /etc/snmp/snmptrapd.conf file and contains just two lines:

disableAuthorization yes
traphandle default /usr/sbin/snmptthandler

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PrestaShop back office error 500 or blank page - Fix it Now ?


This article covers methods to resolve PrestaShop back office error 500.

The error happens when the Back-office is accessed only from Debug mode activated or in production mode activated. The characteristic of this error is that it only occurs in one of the modes and not in both.

Also, this is an error that is occurring ONLY IN PRESTASHOP STORES VERSION 1.7, and that makes it impossible for us to enter the Back-office, showing an error 500 or the page goes blank. 

That's why we call it a critical mistake, for leaving the store inoperative.


To fix a HTTP 500 error on PrestaShop online store website:

You can activate your web host's FTP or CPanel error reports in your PrestaShop shop.

1.  From PrestaShop v1.4 to v1.5.2

i. Open config/config.inc.php

ii. On line 29, you will find this line: @ini_set('display_errors','off');

iii. Replace it with: @ini_set('display_errors','on');


2. PrestaShop v1.5.3 and later versions (including 1.6 and 1.7)

i. Open config/defines.inc.php

ii. On line 28, you will find this line: define('_PS_MODE_DEV_', false);

iii. Replace it with: define('_PS_MODE_DEV_', true);

Once error reports from the FTP or CPanel are activated, you can browse your store's front or back office to find out what the problem is.


More about Server error 500:

Error 500 means Internal server Error. Whenever a 500 error occurs, the task to return information by the server to the web browser will stop. 

Therefore, as we mentioned above, this is a critical error that would leave the website inoperative.

The 500 errors, as we noted above, are internal server errors and their origin may be in a programming code error on any item that is included and related to the request for information returned by the server to the web browser. 

Therefore, not all 500 errors come from the same source.

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WordPress error "Your Connection Is Not Private" - Fix it Now ?


As a result of the SSL connection, sensitive information is protected from being stolen while being transferred between the server and the browser, which is one step in hardening your WordPress security

"Your Connection Is Not Private Error" message means that Google Chrome is preventing you from visiting your site because it is untrusted.

Ultimately, the chrome browser prevents you from gaining access to your website because the SSL certificates cannot be validated.

Typically, the "connection is not private" error in google chrome originates from issues from the side of the client, or from problems with the site's certificate.


To Fix Your Connection Is Not Private WordPress Error:

1. Reload the page

2. Check your network connection

3. Set time and date on your computer

4. Try browser's incognito mode

5. Clear your Browser Cookies, Cache, and History 

6. Disable Antivirus Temporarily

7. Update your Operating System

8. Restart your Computer

Rebooting your device will help clear out the temporary cache. 

This could surely very well fix your issue.

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Windows error "The volume does not contain a recognized file system" - Fix it Now ?


This article covers methods to fix 'The volume does not contain a recognized file system' the Windows error for our customers.

What Caused The Volume Does Not Contain the Recognized File System Error ?

Here are some of the reasons that can cause the error occurs on devices:
1. System re-installation
2. Presence of virus or malware
3. Unsafe system shut down.
4. Failure of file system conversion
5. Deletion of essential system files by mistake
6. Presence of bad sectors
7. Users misapplication
8. Virus/Trojan infection
9. Insufficient power supply

To fix this Windows error:

1. Proceed to Start and click on My Computer or This PC.
2. Select that drive that is not accessible and then choose Properties by right-clicking it.
3. From the Properties window, select the Tool tab and click on the Check button from the Error checking.
4. Select the Scan Drive option.
Once the scanning process is complete, please go back to This PC or My Computer to check whether the drive is fixed or not.

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Shopify error 429 too many requests - Fix it Now ?


This article covers Shopify error 429 too many requests. Basically, 429 too many requests can trigger due to increased number of API requests.
Calls to the REST Admin API are governed by request-based limits, which means you should consider the total number of API calls your app makes.

In addition, there are resource-based rate limits and throttles.

To avoid rate limit errors in Shopify:

Designing your app with best practices in mind is the best way to avoid throttling errors.
1. Optimize your code to only get the data that your app requires.
2. Use caching for data that your app uses often.
3. Regulate the rate of your requests for smoother distribution.
4. Include code that catches errors. If you ignore these errors and keep trying to make requests, then your app won’t be able to gracefully recover.
5. Use metadata about your app's API usage, included with all API responses, to manage your app’s behavior dynamically.
6. Your code should stop making additional API requests until enough time has passed to retry.

The recommended backoff time is 1 second.

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Enable CDN in Prestashop and Resolve related issues - How to do it ?


This article covers how to enable CDN on PrestaShop for our customers.
You can Speed up your website with the PrestaShop CDN addon.
Faster loading leads immediately to happier users and higher conversions.
Making your pages load faster will also improve your SEO.
Google ranks faster websites higher, so you'll soon receive more visitors from search engines.

To How to Enable CDN for Prestashop:

1. Make sure Prestashop is installed and work normally.
2. Login to Prestashop admin panel (e.g. http://prestashop.testing.com.my/admin1234/)
3. Navigate to Advanced Parameters > Performance.
4. Scroll down the page to Media servers and fill in the CDN hostname.
5. Click Save at the top right corner to save the setting.

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Error: Function lookup() did not find a value for the name DEFAULT_EXEC_TIMEOUT


This article covers how to fix this issue found while installing OpenStack with packstack.
In the case you installed packstack with epel repo enabled, you need to uninstall it and all the dependences, and re-install it after disabling epel, so all the proper versions of dependencies are installed correctly.
1. To begin, ensure that epel repo is disabled and try again.
2. Run the following commands:

# yum autoremove epel-release
# yum autoremove openstack-packstack
# yum clean all
# yum install -y openstack-packstack

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WordPress error 'Another update currently in process' – Fix it Now ?


This article covers how to resolve WordPress error 'Another update currently in process'.
Basically, this issue usually occurs when a WordPress user, or multiple users, are simultaneously trying to perform a WordPress update while a WordPress core update is running.
During a core update, an additional row called core_updater.lock is placed within the wp_options table of the website’s database. It serves to prevent any other updates from being run while the core update is in progress.
After the WordPress core has been updated, the core_updater.lock row will be deleted, which will allow users to perform any other updates.
The error message will disappear then, or it will be gone automatically after 15 minutes.

To fix this WordPress error:

1. Log into the WordPress administration dashboard and select Plugins > Add New. Search for Fix Another Update, then install and activate the plugin.
2. Navigate to Settings > Fix Another Update In Progress and the database lock will be removed.
3. If you wish to remove the lock directly in the database, Select Databases > phpMyAdmin from the cPanel menu.
4. Select your WordPress database from the sidebar, then click the Browse button next to the wp_options database table (your database prefix may be different).
5. In the database rows that appear, look for an entry called ‘core_updater.lock’ and select the Delete button to remove. You can now proceed with your outstanding updates.

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Securing Web Servers from DoS attacks - Best Practices ?


This article covers Tactics To Prevent DDoS Attacks & Keep Your Website Safe.
Basically, it is impossible to prevent DoS and DDoS attacks entirely. But we can limit them to a certain extend by implementing security actions mentioned in this guide.
Denial of service attacks are here to stay, and no business can afford to be unprotected.

Facts about DDoS Attacks:
1. DDoS stands for Distributed Denial of Service.
2. It is a form of cyber attack that targets critical systems to disrupt network service or connectivity that causes a denial of service for users of the targeted resource.
3. A DDoS attack employs the processing power of multiple malware-infected computers to target a single system.

Best Practices for Preventing DDoS attacks:

1. Develop a Denial of Service Response Plan
Develop a DDoS prevention plan based on a thorough security assessment. Unlike smaller companies, larger businesses may require complex infrastructure and involving multiple teams in DDoS planning.
2. Secure Your Network Infrastructure
Mitigating network security threats can only be achieved with multi-level protection strategies in place.
This includes advanced intrusion prevention and threat management systems, which combine firewalls, VPN, anti-spam, content filtering, load balancing, and other layers of DDoS defense techniques.
3. Practice Basic Network Security
The most basic countermeasure to preventing DDoS attacks is to allow as little user error as possible.
Engaging in strong security practices can keep business networks from being compromised.
4. Maintain Strong Network Architecture
Focusing on a secure network architecture is vital to security. Business should create redundant network resources; if one server is attacked, the others can handle the extra network traffic.
5. Leverage the Cloud
Outsourcing DDoS prevention to cloud-based service providers offers several advantages. First, the cloud has far more bandwidth, and resources than a private network likely does. With the increased magnitude of DDoS attacks, relying solely on on-premises hardware is likely to fail.

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Install Bcrypt in Docker and resolve related errors


This article covers how to install Bcrypt in Docker and fix relating Docker errors.

To fix bcrypt error on Docker:

The error looks like this,

internal/modules/cjs/loader.js:807
app_1 | return process.dlopen(module, path.toNamespacedPath(filename));

To resolve, simply Add the following lines of code to the start.sh file,

#!/usr/bin/env bash

# install new dependencies if any
npm install
# uninstall the current bcrypt modules
npm uninstall bcrypt
# install the bcrypt modules for the machine
npm install bcrypt
echo "Starting API server"
npm start

Here,

i. npm uninstall bcrypt would remove bcrypt modules for the other operating system.
ii. npm install bcrypt would install for the current machine that the app would be running on.

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Manage Transaction Log File during Data Load - Do it Now


This article covers how to manage transaction log files in SQL Server for our customers. A transaction log is a file – integral part of every SQL Server database. It contains log records produced during the logging process in a SQL Server database.

The transaction log is the most important component of a SQL Server database when it comes to the disaster recovery – however, it must be uncorrupted.

The only way to truncate the log, so the space can be reused, is to perform a SQL transaction log backup. Therefore the most common reason for a transaction log file to have grown extremely large is because the database is in the FULL recovery model and LOG backups haven't been taken for a long time.


How do I stop a transaction log from filling up?

1. To keep the log from filling up again, schedule log backups frequently. 

2. When the recovery mode for a database is set to Full, then a transaction log backup job must be created in addition to backing up the database itself.


To fix a transaction log for a database is full:

1. Backing up the log.

2. Freeing disk space so that the log can automatically grow.

3. Moving the log file to a disk drive with sufficient space.

4. Increasing the size of a log file.

5. Adding a log file on a different disk.

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Nagios No lock file found - Fix this error now


This article covers different methods to resolve the error, Nagios: No lock file found.  Basically, "No lock file found in /usr/local/nagios/var/nagios.lock" means that the service isn't running.

To fix this Nagios error:
Execute the command:

$ /usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg

Running the command above simply starts the nagios daemon and points it to a specific config file.
The advantage to running this command manually over systemd is that when you run "service nagios start" this typically calls the /etc/rc.d/init.d/nagios script which contains a line with parametrized environment variables:

$NagiosBin -d $NagiosCfgFile

Because every system is different, not specifying either the bin nor config directories could lead to nagios breaking (stopping) when it tries to start using the default installation directory paths

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Updating Windows VM Templates on VMWare with PowerShell - How to do it


This article covers how to update Windows VM Templates on VMWare. 

The update process of a VM template on VMWare consists of the following stages:

1. A template from the Content Library is converted to a virtual machine.;

2. After starting it, an administrator logs on, installs approved Windows updates using WSUS, updates the required software;

3. After the updates have been installed, the VM is restarted, then turned of and converted back to the template.

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Virtualization Restrictions in RedHat Linux with KVM


This article covers Virtualization Restrictions in RedHat Linux which are additional support and product restrictions of the virtualization packages.


The following notes apply to all versions of Red Hat Virtualization:

1. Supported limits reflect the current state of system testing by Red Hat and its partners. Systems exceeding these supported limits may be included in the Hardware Catalog after joint testing between Red Hat and its partners. If they exceed the supported limits posted here, entries in the Hardware Catalog are fully supported. In addition to supported limits reflecting hardware capability, there may be additional limits under the Red Hat Enterprise Linux subscription terms. Supported limits are subject to change based on ongoing testing activities.


2. These limits do not apply to Red Hat Enterprise Linux (RHEL) with KVM virtualization, which offers virtualization for low-density environments.


3. Guest operating systems have different minimum memory requirements. Virtual machine memory can be allocated as small as required.

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Remove Nginx on linux in Vesta control panel - Step by Step process to do it


This article covers how to remove Nginx on Linux in the Vesta control panel. 

Vesta control panel (VestaCP) is an open source hosting control panel, which can be used to manage multiple websites, create and manage email accounts, FTP accounts, and MySQL databases, manage DNS records and more.


To uninstall VestaCP on CentOS, follow the steps below:

1. Connect to your server via SSH as root

2. Stop the Vesta service with service vesta stop:

$ service vesta stop 

3. Delete Vesta packages/software repository:

# yum remove vesta*

and

# rm -f /etc/yum.repos.d/vesta.repo

4. You may also want to remove /usr/local/vesta folder:

# rm -rf vesta

5. Now we have to remove the cron jobs for the user admin.

Let's list first the cron jobs:

# crontab -u admin -l
MAILTO=admin@ibmimedia.com
CONTENT_TYPE="text/plain; charset=utf-8"
15 02 * * * sudo /usr/local/vesta/bin/v-update-sys-queue disk
10 00 * * * sudo /usr/local/vesta/bin/v-update-sys-queue traffic
30 03 * * * sudo /usr/local/vesta/bin/v-update-sys-queue webstats
*/5 * * * * sudo /usr/local/vesta/bin/v-update-sys-queue backup
10 05 * * * sudo /usr/local/vesta/bin/v-backup-users
20 00 * * * sudo /usr/local/vesta/bin/v-update-user-stats
*/5 * * * * sudo /usr/local/vesta/bin/v-update-sys-rrd
40 2 * * * sudo /usr/local/vesta/bin/v-update-sys-vesta-all
03 3 * * * sudo /usr/local/vesta/bin/v-update-letsencrypt-ssl

6. Remove the cron jobs via crontab -u admin -e:

# crontab -u admin -e

7. Save and exit:


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Configure PostgreSQL on Linux in Vesta control panel - How to do it


This article covers how to install and setup PostgreSQL on Vesta Control panel running RHEL, CentOS, Debian, or Ubuntu server. PostgreSQL is an advanced version of SQL which provides support to different functions of SQL like foreign keys, subqueries, triggers, and different user-defined types and functions.


To set up PostgreSQL on a RHEL or CentOS:

1. Install PostgreSQL packages

yum install postgresql postgresql-server postgresql-contrib phpPgAdmin

* If you have remi installed then don't forget to explicitly enable it.

yum install --enablerepo=remi postgresql postgresql-server postgresql-contrib phpPgAdmin


2. Initialize database cluster

service postgresql initdb


3. Download hba configuration

wget http://c.vestacp.com/0.9.8/rhel/pg_hba.conf -O /var/lib/pgsql/data/pg_hba.conf


4.  Start the server

service postgresql start


5. Set oracle user password

su - postgres

psql -c "ALTER USER postgres WITH PASSWORD 'pgp4sw0rd'"

exit


6. Enable pgsql databases support in vesta.

open /usr/local/vesta/conf/vesta.conf and set DB_SYSTEM to 'mysql,pgsql'


7. Register pg instance in control panel

v-add-database-host pgsql localhost postgres pgp4sw0rd


8. Download phpPgAdmin configuration

wget http://c.vestacp.com/0.9.8/rhel/pga.conf -O /etc/phpPgAdmin/config.inc.php

wget http://c.vestacp.com/0.9.8/rhel/httpd-pga.conf -O /etc/httpd/conf.d/phpPgAdmin.conf


9. Restart web server

service httpd restart


To set up PostgreSQL on a Debian or Ubuntu:

1. Install PostgreSQL packages

apt-get install postgresql postgresql-contrib phppgadmin


2. Download hba configuration

wget http://c.vestacp.com/0.9.8/debian/pg_hba.conf -O /etc/postgresql/*/main/pg_hba.conf


3. Restart the server

service postgresql restart


4. Set oracle user password

su - postgres

psql -c "ALTER USER postgres WITH PASSWORD 'pgp4sw0rd'"

exit


5. Enable pgsql databases support in vesta.

open /usr/local/vesta/conf/vesta.conf and set DB_SYSTEM to 'mysql,pgsql'


6. Register pg instance in control panel

v-add-database-host pgsql localhost postgres pgp4sw0rd


7. Download phpPgAdmin configuration

wget http://c.vestacp.com/0.9.8/debian/pga.conf -O /etc/phppgadmin/config.inc.php

wget http://c.vestacp.com/0.9.8/debian/apache2-pga.conf -O /etc/apache2/conf.d/phppgadmin


8. Restart web server

service apache2 restart

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Server Hardening - What it means


This article covers techniques to prevent attacks on the server. Basically, if we manage our servers without proper precautionary actions it is easy to spoil the reputation of the server.

Hardening your server is the process of increasing security on your server through a variety of means to result in a much more secure operating environment. Server hardening is one of the most important tasks to be handled on your servers. 

The default configuration of most operating systems is not designed with security as the primary focus. 

Default server setups focus more on usability, functionality and communication.


Server Hardening Security Measures Includes:

1. Hide login password from cgi scripts.

This setting allows you to hide the REMOTE_PASSWORD variable from scripts that the cpsrvd daemon's CGI handler executes.

2. Referrer safety check.

Only permit cPanel, Webmail and WHM to execute functions when the browser-provided referrer (port and domain or IP address) exactly matches the destination URL.

3. Initial default/catch-all forwarder destination

Select Fail to automatically discard un-routable email that your servers new accounts receive. This will help protect your server from mail attacks.

4. Verify signatures of third-party cPaddons.

Enable this option to verify GPG signatures of all third-party CPaddons.

5. Prevent "nobody" from sending mail.

Enable to block email that the nobody user sent to the remote address. Nobody is the username for Apache.

6. Enable SPF on domains for newly created accounts.

7. Proxy subdomain override.

Disable this option to prevent automatically-generated proxy domains when a user creates a subdomain.

8. Proxy subdomain creation.

Disable this option to prevent the addition of cPanel, Webmail, Web Disk and WHM proxy subdomain DNS entries to new accounts.

9. Cookie IP validation.

Disable this option to allow logins regardless of the user's IP address.

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Show dropped packets per interface on Linux - Methiods to check it


This article covers how to Show dropped packets per interface on Linux. 

There can be various reasons for packet loss. It can be that the network transport is unreliable and packet loss is natural, the network link could be congested, applications cannot handle the offered load.

Sometimes there are too many packets, they are saved to a buffer, but they are saved faster than processed, so eventually the buffer runs out of space, so the kernel drops all further packets until there is some free space in the buffer.


You will learn the different Linux commands to see packet loss on Linux per-interface, including excellent tools such as dropwatch. 

We can also use Linux profiling with performance counters utility called perf.


To display show dropped packets per interface on Linux using the netstat:

The netstat command is mostly obsolete. Replacement for netstat is ss and ip command. 

However, netstat still available on older Linux distros, which are in productions. 

Hence, I will start with netstat but if possible, use the ip/ss tools. 

The command in Linux is:

$ netstat -i

$ netstat --interfaces


To display summary statistics for each protocol, run:

$ netstat -s

$ netstat --statistics


To show dropped packets statistics per network interface on Linux using the ip:

Let us see how to see link device stats using the ip command. 

The syntax is:

$ ip -s link

$ ip -s link show {interface}

$ ip -s link show eth0

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Log Suspicious Martian Packets Un-routable Source Addresses in Linux


This article covers how to block and log suspicious martian packets on Linux servers.


Log Suspicious Martian Packets in Linux:

On the public Internet, such a packet's (Martian) source address is either spoofed, and it cannot originate as claimed, or the packet cannot be delivered. 

Both IPv4 and IPv6, martian packets have a source or destination addresses within special-use ranges as per RFC 6890.


Benefits of logging of martians packets:

As I said earlier a martian packet is a packet with a source address that cannot be routed over the public Internet. 

Such a packet is waste of resources on your server. 

Often martian and unroutable packet used for a dangerous purpose or DoS/DDOS your server. 

So you must drop bad martian packet earlier and log into your server for further inspection.


To log Martian packets on Linux?

You need to use sysctl command command to view or set Linux kernel variables that can logs packets with un-routable source addresses to the kernel log file such as /var/log/messages.


To log suspicious martian packets on Linux:

You need to set the following variables to 1 in /etc/sysctl.conf file:

net.ipv4.conf.all.log_martians

net.ipv4.conf.default.log_martians


Edit file /etc/sysctl.conf, enter:

# vi /etc/sysctl.conf

Append/edit as follows:

net.ipv4.conf.all.log_martians=1 

net.ipv4.conf.default.log_martians=1


Save and close the file.

To load changes, type:

# sysctl -p

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Unable to add MySQL database in Plesk Customer Panel - Fix it now


This article covers how to fix issues that make it unable to add MySQL database in Plesk customer panel.


To resolve Cannot add MySQL database in Plesk Customer Panel:

1. Log in to Plesk and apply one of the following:

2. Enable Database server selection directive in Service Plans > Default > Permissions > Show more available permissions and press Update & Sync.

3. Switch MySQL default database server from None to localhost:3306 in Service Plans > Default > Hosting Parameters > Default Database Server and press Update & Sync.


Note:  it is also applicable to cases when Amazon RDS extension is installed. 

If it is needed to provide customer with the ability to select Amazon server, enable "database server selection" option.


How do I add a database to my Plesk Panel?

How to Create a New Database or Database User in the Plesk Control Panel

1. Log into your Control Panel.

2. Click on Databases.

3. Click on the Add New Database icon.

4. Next to Database Name enter the name you want to use.

For Type, choose either Microsoft SQL Server or MySQL (DNN uses the Microsoft SQL Server.).

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Configure Varnish with Apache - How to do it


This article covers how to configure Varnish #cache on the #Apache server. Varnish is an HTTP accelerator and a useful tool for speeding up a server, especially during a times when there is high traffic to a site. 

It works by redirecting visitors to static pages whenever possible and only drawing on the virtual private server itself if there is a need for an active process.

#Varnish is a caching HTTP reverse proxy. It receives requests from clients and tries to answer them from the cache.


Where is varnish configuration file?

The Varnish configuration file will be located in the /etc/varnish directory in CentOS 7. 

To make Varnish work in front of Apache, you will need to set up some basic configurations. 

By default Varnish listens on port 6081 . 

You will need to change port 6081 to 80 so that website requests access the Varnish cache first.


What is varnish WordPress?

Varnish is a full-page cache and HTTP preprocessor which can be used to speed up requests for a WordPress site. 

Setting up Varnish is a technical task, as it requires installing and configuring a system package on a web server, rather than just installing a plugin.

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Methods to secure database server - Best Practices


This article covers different methods to secure a Database Server. Database security helps: Company's block attacks, including ransomware and breached firewalls, which in turn keeps sensitive information safe. It Prevent malware or viral infections which can corrupt data, bring down a network, and spread to all end point devices.


SQL injection vulnerabilities occur when application code contains dynamic database queries which directly include user supplied input. 

This is a devastating form of attack and BSI Penetration Testers regularly find vulnerable applications that allow complete authentication bypass and extraction of the entire database.

SQL injection, also known as SQLI, is a common attack vector that uses malicious SQL code for backend database manipulation to access information that was not intended to be displayed. 

This information may include any number of items, including sensitive company data, user lists or private customer details.


Some known database security issues:

Security risks to database systems include,

1. Data corruption and/or loss caused by the entry of invalid data or commands

2. Mistakes in database or system administration processes, sabotage/criminal damage and so on.


There are numerous types of databases and many different ways to hack them, but most hackers will either try to crack the database root password or run a known database exploit. 

If you're comfortable with SQL statements and understand database basics, you can hack a database.


Practices for Database Security:

1. Protect Against Attacks With a Database Proxy.

2. Set Up Auditing and Robust Logging.

3. Practice Stringent User Account Management.

4. Keep Your Database Software and OS Up-to-Date.

5. Encrypt Sensitive Data in Your app, in Transit, and at Rest.

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MongoDB error topology was destroyed - Fix it now


This article covers method to fix the error 'MongoDB error topology was destroyed' which happens due to many reasons that include interruption of the node server’s connection to the MongoDB instance while it was trying to write to it. If the mongo driver drops the connection for any reason.
Another reason could be mongoose disconnecting before the creation of mongo document indexes.
You might try updating mongo.
There's also a mongo config setting that can easily in the database using too much memory and being killed by the kernel.

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DirectAdmin error is not a valid username


This article covers tips to resolve DirectAdmin error: is not a valid username which happens if the username length of the account is larger than the value set in the DirectAdmin configuration file.
To fix DirectAdmin Admin Backup/Transfer restore error with no details,  try to restore to a number than 10 characters.
You have to edit directadmin configuration and set this variable.
[root@mx ~]# vi /usr/local/directadmin/conf/directadmin.conf
then edit max_username_length to larger value. I my example 20.
max_username_length=20

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Tips to secure mail server


This article covers some tips to secure a mail server.

Email on the internet is sent by the Simple Mail Transfer Protocol (SMTP). Where a mail flow between servers is not encrypted, it could be intercepted by an ISP or government agency and the contents can be read by passive monitoring.
Basically, When emails are sent between two parties, unless BOTH parties use encryption the message is open and can be read by anyone who intercepts it.
Any emails sent to and received from mailboxes that only send cleartext emails should be considered as security liabilities.

Tips on how to secure your mail server:
1. Encryption: When securing your mail server, make sure you are using secure connections. Encrypt POP3 and IMAP authentication and use SSL and TLS.

2. Mail relay configuration: Avoid being an open relay for spammers by specifying which domains/IP addresses your mail server will relay mail for.

3. Connections and default settings: To avoid DoS attacks, limit the number of connection and authentication errors that your systems will accept. Remove unneeded server functionality by disabling any unnecessary default settings. Have a dedicated mail server and move other services like FTP to other servers. Keep total, simultaneous, and maximum connections to your SMTP server limited.

4. Access Control: To protect your server from unauthorized access, implement authentication and access control. For example, SMTP authentication requires users to supply a username and password to be able to send mail from the server. Make sure access to your servers is on a need-to-have basis and is shared with as few people as possible.

5. Abuse prevention: Check DNS-based blacklists (DNSBLs) and reject email from any domains or IPs listed on them. Check Spam URI Real-time Blocklists (SURBL), and reject any messages containing invalid or malicious links.
Also, maintain a local blacklist and block any IP addresses that specifically target you. Employ outbound filtering and use CAPTCHA/reCAPTCHA with your web forms.

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Malicious TMP files and processes


This article covers method to resolve malicious tmp processes. Most malware installers delete itself and these TMP files after successful installation.
The use of TMP files for atomicity is an advantage attackers currently enjoy.
They could have done this operation in any folder of the system, but they choose to use the standard Windows Temp folder.
The first thing a malware installer (first stage of infection) does when executed on a target system - be it a dropper or downloader - is to install a copy of the malware and its components into their corresponding location in the system.

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Hardening an Ubuntu Server


This article covers the the importance of passwords, user roles, console security, and #firewalls all of which are imperative to protecting Linux servers.
Hardening an #Ubuntu server is a critical step in any server setup procedure.
Any time that a new server is being brought up to host services, whether production, development, internal or external, the server's operating system must be made as secure as possible.


To make your Ubuntu #Linux server secure:
1. Secure Server Connectivity
2. Establish and Use a Secure Connection.
3. Use SSH Keys Authentication.
4. Secure File Transfer Protocol.
5. Secure Sockets Layer Certificates.
6. Use Private Networks and VPNs.
7. Monitor Login Attempts.
8. Manage Users.
9. Establish Password Requirements.

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Install Linux Software Via Command line


This article will guide you on methods to install #Linux #Software via command line. #Debian, Ubuntu, Mint, and other Debian-based distributions all use . deb files and the dpkg package management system. There are two ways to install apps via this system. You can use the apt application to install from a repository, or you can use the dpkg app to install apps from .


To compile a program from a source in Linux:

i. Open a console.

ii. Use the #command cd to navigate to the correct folder. If there is a README file with installation instructions, use that instead.

iii. Extract the files with one of the commands.

iv. ./configure.

v. make.

vi. sudo make install (or with checkinstall ).


To Check os version in Linux:

1. Open the #terminal application (bash shell)

2. For remote server login using the ssh: ssh user@server-name.

3. Type any one of the following command to find os name and version in Linux: cat /etc/os-release. lsb_release -a. hostnamectl.

4. Type the following command to find Linux kernel version: uname -r.

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Back Pressure in Exchange server


This article will guide you on Back Pressure which is a feature that helps the Transport Service monitor system resources and stop message submission when it runs low on resources. 

Microsoft Exchange Transport Service Resource Monitoring.

Microsoft Exchange enables email to be delivered directly to a server. 

It works by sending the emails back to your individual workstations in which your staff can access. 

Small and medium-sized companies can achieve three benefits from using Microsoft Exchange. 

Centralize emails so that they can be backed up.


Exchange server roles:

1. Mailbox servers contain the transport services that are used to route mail.

2. Mailbox servers contain mailbox databases that process, render, and store data.

3. Mailbox servers contain the Client Access services that accept client connections for all protocols.

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Troubleshoot Azure Cache for Redis timeouts


This article will guide you on how to troubleshoot Azure #Cache for Redis #timeouts. Azure Cache for Redis regularly updates its server software as part of the managed service functionality that it provides. 

Azure Cache for #Redis is a fully managed, in-memory cache that enables high-performance and scalable architectures. Use it to create cloud or hybrid deployments that handle millions of requests per second at sub-millisecond latency—all with the configuration, security, and availability benefits of a managed service.

This patching activity takes place largely behind the scene. During the failovers when Redis server nodes are being patched, Redis clients connected to these nodes may experience temporary timeouts as connections are switched between these nodes.


To help mitigate #Azure memory issues:

1. Upgrade the cache to a larger size so that you aren't running against memory limitations on the system.

2. Set expiration times on the keys so that older values are evicted proactively.

3. Monitor the used_memory_rss cache metric. When this value approaches the size of their cache, you're likely to start seeing performance issues. Distribute the data across multiple shards if you're using a premium cache, or upgrade to a larger cache size.


To fix #CPU bound on the server or on the client:

i. Check if you're getting bound by CPU on your client. High CPU could cause the request to not be processed within the synctimeout interval and cause a request to time out. 

ii. Moving to a larger client size or distributing the load can help to control this problem.

iii. Check if you're getting CPU bound on the server by monitoring the CPU cache performance metric. Requests coming in while Redis is CPU bound can cause those requests to time out. To address this condition, you can distribute the load across multiple shards in a premium cache, or upgrade to a larger size or pricing tier.

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ACK scan DOS attack


This article will guide you on how the ACK scan DOS #attack works as well as methods to mitigate this. 

A port scan can help an attacker find a weak point to attack and break into a computer system. 

Just because you've found an open port doesn't mean you can attack it. But, once you've found an open port running a listening service, you can scan it for vulnerabilities.

Denial of service attack (DOS) is an attack against computer or network which reduces, restricts or prevents accessibility of its system resources to authorized users. The network of Bots is called botnet.

A Fraggle Attack is a denial-of-service (#DoS) attack that involves sending a large amount of spoofed UDP traffic to a router's broadcast address within a network. 

It is very similar to a Smurf Attack, which uses spoofed ICMP traffic rather than UDP traffic to achieve the same goal.

Common DoS attacks:

1. Buffer overflow attacks – the most common DoS attack.

2. ICMP flood – leverages misconfigured network devices by sending spoofed packets that ping every computer on the targeted network, instead of just one specific machine.

3. SYN flood – sends a request to connect to a server, but never completes the handshake.

To prevent port scan attacks:

i. Install a Firewall: A firewall can help prevent unauthorized access to your private network.

ii. TCP Wrappers: TCP wrapper can give administrators the flexibility to permit or deny access to the servers based on IP addresses or domain names.

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DEBIAN_FRONTEND noninteractive in Docker


This article will guide you on why you should not set the DEBIAN_FRONTEND value to noninteractive is a 'cosmetic' change. If you really need to change its setting, make sure to change it back to its default value afterward. Simply prepending an apt command with DEBIAN_FRONTEND=something does not persist after the single command to which it is applied. 

apt-get update downloads the package lists from the repositories and "updates" them to get information on the newest versions of packages and their dependencies. 

It will do this for all repositories and PPAs.

To Preserve Configuration Files:

During package installation or upgrade, Debian may wish to prompt the user on overwriting a configuration file. 

This preference can be appended to the installation command:

apt-get install -q -y \
-o Dpkg::Options::="--force-confdef" \
-o Dpkg::Options::="--force-confold" \
postfix

This command will instruct the installer to quiet any messages, assume yes, and then upgrade configuration files if no changes are present in the new package.

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IMAP server wants to alert you to the following error


This article will guide you the different causes for the error 'your IMAP server wants to alert you to the following'.

IMAP #Error code #0x800cccdd appears alongside the message "Your IMAP server closed the connection", which signifies that the "Send/Receive" feature—a setting that retrieves your #Outlook mail whenever connected to the Internet in order to keep your mail synced—has failed.

The error message "Your account temporarily blocked for #IMAP use. This may be happen if you exceed the maximum number of simultaneous IMAP connections allowed. Kindly try after some time" occurs when the mail client or different mail clients are trying to establish too many connections to IMAP server.

A server connection timeout means that a server is taking too long to reply to a data request made from another device. Timeouts are not a reply message: they show up when there isn't a reply and a server request is not fulfilled in a predetermined length of time.

To fix the mail server is not responding:

1. Check your internet connection.

2. Check your #SMTP server details.

3. Verify all usernames and passwords.

4. Check your SMTP server connection.

5. Change your SMTP port.

6. Control your #antivirus or #firewall settings.

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ACK flood DDoS attack


This article will guide you on methods to prevent ACK flood #DDoS #attack. An ACK flood DDoS attack occurs when an attacker attempts to overload a server with TCP ACK packets. 

Client requests connection by sending #SYN (synchronize) message to the server. Server acknowledges by sending SYN-ACK (synchronize-acknowledge) message back to the client. Client responds with an #ACK (acknowledge) message, and the connection is established.

When computers communicate via TCP, received packets are acknowledged by sending back a packet with an ACK bit set. 

The TCP protocol allows these acknowledgements to be included with data that is sent in the opposite direction. 

Some protocols send a single acknowledgement per packet of information.

To stop a SYN #DDoS attack:

1. Filtering.

2. Increasing Backlog.

3. TCP half-open: The term half-open alludes to TCP associations whose state is out of synchronization between the two potentially because of an accident on one side.

4. Firewalls and Proxies.

5. Reducing SYN-RECEIVED Timer.

6. SYN Cache.

7. Recycling the Oldest Half-Open TCP.

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NTP amplification attack


This article will guide you on steps to mitigate this #NTP amplification attack. An Amplification Attack is any attack where an attacker is able to use an amplification factor to multiply its power. Examples of #amplification #attacks include Smurf Attacks (ICMP amplification), Fraggle Attacks (#UDP amplification), and DNS Amplification.

DNS flood is a type of Distributed Denial of Service (#DDoS) attack in which the attacker targets one or more Domain Name System (#DNS) servers belonging to a given zone, attempting to hamper resolution of resource records of that zone and its sub-zones.

To harden your DNS server:

1. Audit your DNS zones. First things first.

2. Keep your DNS servers up-to-date.

3. Hide BIND version.

4. Restrict Zone Transfers.

5. Disable DNS recursion to prevent DNS poisoning attacks.

6. Use isolated DNS servers.

7. Use a DDOS mitigation provider.

8. Two-Factor Authentication.

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WordPress Error Briefly Unavailable for Scheduled Maintenance


This article will guide you on how to #fix 'Briefly unavailable for scheduled maintenance' #error in WordPress. 

To take your site out of #maintenance mode and get rid of the “Briefly unavailable for scheduled maintenance. Check back in a minute” message, all you need to do is delete that . maintenance file.

There are many reasons a site might not load such as a misconfiguration, corrupt files, problems with a database or something as simple as needing to clear your browser's cache and cookies on your computer.

To place your #WordPress Website down for maintenance:

1. First, you need to select the status. You can select 'Enable Coming Soon Mode' or 'Enable Maintenance Mode'. 

2. You can also select redirect mode which allows you to simply redirect your users to some other website. 

3. After choosing maintenance or coming soon mode, click on the 'Save all changes' button.

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Enable FirewallD logging for denied packets on Linux


This article will guide you on how to enable #FirewallD logging for denied packets on #Linux. It is an important task to keep an eye on the rejected and dropped packets using FirewallD for #Linux system administrators. 

To enable logging option you need to use #LOG iptables/kernel module. It turn on kernel logging of matching packets. When this option is set for a rule, the Linux kernel will print some information on all matching packets (like most IP header fields) via the kernel log.

To log a dropped packet in iptables:

1. iptables -N LOGGING: Create a new chain called LOGGING.

2. iptables -A INPUT -j LOGGING: All the remaining incoming packets will jump to the LOGGING chain.

3. line#3: Log the incoming packets to syslog (/var/log/messages).

To  restart iptables:

i. To start firewall from a shell enter: # chkconfig iptables on. # service iptables start.

ii. To stop firewall, enter: # service iptables stop.

iii. To restart #firewall, enter: # service iptables restart.

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Memcached DDOS attack


This article will guide you on methods to mitigate Memcached DDOS attacks which occur mostly by accident. To mitigate this attack, you can Disable #UDP, #Firewall #Memcached servers, and so on.

 DoS attack is a denial of service attack where a computer is used to flood a server with TCP and UDP packets. A DDoS attack is where multiple systems target a single system with a DoS attack. The targeted network is then bombarded with packets from multiple locations.

DDoS attacks are illegal under the Computer Fraud and Abuse Act. Starting a DDoS attack against a network without permission is going to cost you up to 10 years in prison and up to a $500,000 fine.

There are three essential security measures that all small businesses should take to protect themselves from #DDoS #attacks: Use a web application firewall (#WAF): The absolute best way to prevent a DDoS attack is through the use of a WAF that blocks bad traffic and prevents DDoS attacks from accessing your web server.

A Denial-of-Service (#DoS) attack is an attack meant to shut down a machine or network, making it inaccessible to its intended users. DoS attacks accomplish this by flooding the target with traffic, or sending it information that triggers a crash.

Different DDoS attack method:

1. UDP flood.

2. ICMP (Ping) flood.

3. SYN flood.

4. Ping of Death.

5. Slowloris.

6. NTP Amplification.

7. HTTP flood.

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Joomla 503 service unavailable


This article will guide you on method to fix #Joomla #503 service unavailable which occurs due to web traffic or bad PHP scripts or corrupted #modules.

A 503 Service Unavailable Error is an HTTP response status code indicating that a server is temporarily unable to handle the request. This may be due to the server being overloaded or down for maintenance. 

To Fix an #HTTP #Error 503:

1. Reboot your server.

2. Check to see if your web server is going through maintenance.

3. Fix faulty firewall configurations.

4. Sift through your server-side logs.

5. Comb through your website's code to find bugs.

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Monitor System Metrics with the TICK Stack on CentOS 7


This article will guide you on how the TICK stack can be a powerful tool for storing, analyzing, and visualizing time series data. To monitor InfluxDB _internal metrics in a production #cluster, use Telegraf and the influxdb input plugin to capture these metrics from the InfluxDB /debug/vars endpoint and store them in an external InfluxDB monitoring instance.

More about Kapacitor:

#Kapacitor is a native data processing engine for #InfluxDB 1. x and is an integrated component in the InfluxDB 2.0 platform. 

Kapacitor can process both stream and batch data from InfluxDB, acting on this data in real-time via its programming language TICKscript.

A retention policy (RP) is the part of InfluxDB data structure that describes for how long InfluxDB keeps data. 

InfluxDB compares your local server's timestamp to the timestamps on your data and deletes data that are older than the RP's DURATION . 

A single database can have several RPs and RPs are unique per database.

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ICMP Flood Attack Methods to mitigate


This article will guide you on methods to mitigate ICMP flood #attack. This is the type of Denial of Service (DoS) attack in which an attacker attempts to crash, destabilize, or freeze the targeted computer or service by sending malformed or oversized packets using a simple ping command.

Many network administrators feel that ICMP is a security risk, and should therefore always be blocked at the firewall. It is true that ICMP does have some security issues associated with it, and that a lot of #ICMP should be blocked. 

But this is no reason to block all ICMP traffic!

To mitigate Ping flood attack:

1. Disabling a ping flood is most easily accomplished by disabling the ICMP functionality of the targeted router, computer or other device. 

2. A network administrator can access the administrative interface of the device and disable its ability to send and receive any requests using the ICMP, effectively eliminating both the processing of the request and the Echo Reply. 

3. The consequence of this is that all network activities that involve ICMP are disabled, making the device unresponsive to ping requests, traceroute requests, and other network activities.

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DNS Amplification Attack


This article will guide you on different methods to mitigate DNS amplification attack. Basically, DDoS attacks can really freeze websites or even cause server downtime. 

DNS flood is a type of Distributed Denial of Service (#DDoS) attack in which the attacker targets one or more Domain Name System (DNS) servers belonging to a given zone, attempting to hamper resolution of resource records of that zone and its sub-zones.

A Domain Name Server (#DNS) Amplification attack is a popular form of Distributed Denial of Service (DDoS), in which attackers use publically accessible open DNS servers to flood a target system with DNS response traffic.

1. UDP reflection attacks exploit the fact that UDP is a stateless protocol.

2. An attacker then sends the UDP packet containing the spoofed source IP to an intermediate server. 

3. The server is tricked into sending its UDP response packets to the targeted victim IP rather than back to the attacker's IP address.

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Copy rds snapshot to s3


This article will guide you on resolve common rds #error. Basically, the process to copy rds snapshot to s3 is simple and creates and saves backups of the DB instance in the Amazon S3 bucket. 

Amazon Relational Database Service (#Amazon RDS) makes it easy to set up, operate, and scale a relational database in the cloud. It provides cost-efficient and resizable capacity while automating time-consuming administration tasks such as hardware provisioning, database setup, patching and backups.

RDS creates a storage volume snapshot of your #DB instance, backing up the entire DB instance and not just individual databases. RDS saves the automated backups of your DB instance according to the backup retention period that you specify.

To copy a #RDS snapshot from one region to another:

1. Create a #snapshot of your RDS.

2. In your newly created snapshot go to Actions -> Copy Snapshot.

3. Click orange View snapshots in destination region.

4. In the target region's snapshots table find your copied snapshot, and wait until status "Copying" becomes "Completed".

5. Select the snapshot, click Actions -> Restore Snapshot.

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Install XRDP Server


This article will guide you on steps to install XRDP #Server on #Ubuntu. To provide remote access via RDP, a Windows native protocol, XRDP behind the scenes uses #VNC, a remote access protocol more common in Linux.

After #xrdp is installed you can start the server with the following command:

Service xrdp start.

Service xrdp-sesman start (Thanks to Greg for pointing that out) — UPDATE!!

If want it to auto start after reboot you need to run this command also: update-rc.d xrdp enable (It will not start xrdp-sesman automatic).


To use XRDP Linux:

1. With #Ubuntu 18.04 first install xrdp: sudo apt-get -y install xrdp.

2. Next, one may adjust the configuration file: sudo nano /etc/xrdp/xrdp.ini.

3. Set encryption level to high: encrypt_level=high.

4. Next, allow just RDP through the local firewall: sudo ufw allow 3389/tcp.

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Install Microsoft PowerShell on Ubuntu


This article will guide you on steps to install PowerShell on #Ubuntu. #PowerShell is a configuration management tool that brings the capabilities of Linux command-line interface (#CLI) control into the historically point-and-click Windows environment to manage Windows servers efficiently in virtual deployments.

With PowerShell and WSL, we can integrate Linux commands into #Windows just as if they were native applications. 

No need to hunt around for Win32 builds of #Linux utilities or be forced to interrupt your workflow to drop into a Linux shell.

To check the PowerShell version installed in your system, you can use either $PSVersionTable or $host command.

To get a list of PowerShell commands:

1. Get-Command gets the commands from #PowerShell modules and commands that were imported from other sessions. 

2. To get only commands that have been imported into the current session, use the ListImported parameter. 

3. Without parameters, Get-Command gets all of the #cmdlets, functions, and aliases installed on the #computer.

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WHM Mail Queue Manager


This article will guide you on use different features available in the #WHM Mail Queue Manager. Basically, the #Mail #Queue Manager feature in WHM is a handy tool that allows us to view, delete, and attempt to deliver queued emails that have not yet left the server. 

Postfix is a free and open-source mail transfer agent (#MTA) that routes and delivers electronic mail.

postfix flush helps to Flush queued mail.

This command will attempt to redeliver all queued mail. Use the command sparingly, multiple flushes will impact the overall performance of your mail server

To check my mail queue in cPanel:

i. Log into WHM.

ii. Go to Main >> Email >> Mail Queue Manager.

iii. You can click on the message to see the details.

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Create a virtual machine using lightsail in AWS


This article will guide you on how to create a virtual #machine using Lightsail in #AWS.

#Lightsail is an easy-to-use virtual private server (#VPS) that offers you everything needed to build an application or website, plus a cost-effective, monthly plan.

To create a virtual machine in #cloud:

1. Using the left-hand navigation bar, click Compute Engine and then select #VM instances from the item list. 

2. If this is your first #VM on the platform. 

3. If you have a VM template you can import it to GCP, but in this case we will create a VM from scratch.

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Install a module in DNN


This article will guide you on how to #install a module in #DNN.

To Install / Update a #DotNetNuke #Module:

1. Log into your site as either HOST or another supersuser level account.

2. Open Settings -> Extensions.

3. Click "install extension".

4. Drag and drop the package into the window, or browse to the desired file to upload it.

5. Click Next, accept the license, continue through the install. When finished click on the Return button.

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Optimize Opencart website speed


This article will guide you on methods to optimize #OpenCart #Website to boost  and improve speed and pages load time.

OpenCart is one of the most recommended e-commerce platforms used by online merchants to set up their digital store. This PHP based platform provides users with an open source solution, allowing users to download and integrate any additional features to optimize one's e-commerce store.

Sometimes #websites load slowly because of the server. How this works is that your browser notifies your server asking it to send the data for your website over, so that the site can load. 

If there is an issue with the server, this will take longer than normal. The cause of slow servers usually lays with the web host.

To increase your Website page #speed:

1. Enable compression.

2. Minify CSS, JavaScript, and HTML.

3. Reduce redirects.

4. Remove render-blocking JavaScript.

5. Leverage browser caching.

6. Improve server response time.

7. Use a content distribution network.

8. Optimize images.

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Microsoft office Error code 1309


This article will guide you on different methods to resolve #Microsoft office Error code 1309. To avoid this error please right click the downloaded file and select “Extract All,” then choose a destination for the files to be extracted to.

If you encountered a problem while installing Office on a PC, try restarting your computer and then attempting to install Office again. If that didn't help, use this easy fix tool to uninstall #Office completely. After your uninstall is complete, try reinstalling Office.

To fix Another installation is already in progress on Windows 10:

1. Restart the #Windows Installer service.

2. End Windows Installer process.

3. Disable Windows Installer service and restart your #PC.

4. Perform Disk Cleanup.

5. Perform a Clean #Boot.

6. Check your #Registry.

7. Uninstall and reinstall Office.

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psql to restore a text dump How to do it


This article will guide you on steps to perform  text dump restoration. Basically, psql restores a text dump in the same file format.

You can backup a single table, a #schema, or a complete database. Select the name of the backup source in the #pgAdmin tree control, right click to open the context menu, and select Backup… to open the #Backup dialog. 

The name of the object selected will appear in the dialog title bar.

In #PostgreSQL, you can restore a database in two ways:

i. Using psql to restore plain #SQL script file generated by pg_dump and pg_dumpall tools.

ii. Using pg_restore to restore tar file and directory format created by the pg_dump tool.


To Restore Postgres Database:

1. Restore a postgres database. $ psql -U erp -d erp_devel -f mydb.sql.

2. Backup a local postgres database and restore to remote server using single command: $ pg_dump dbname | psql -h hostname dbname.

3. Restore all the postgres databases.

4. Restore a single postgres table.

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Effective methods to control bounce back email messages


This article will guide you on how to control #bounce back #email #messages. Email bounce back is the condition when emails fail to reach the recipient’s inbox. 

The accepted benchmark for bounced emails is 2%. This means for every 100 emails you send, two will be returned to you. Often times, your bounce rate will be much lower. Anything between 2% and 5% is worth noting.

On average maintaining a lower bounce rate is an essential part of your SEO. Normally, your bounce rate should be between 26% - 70%. On average you should maintain between 41% - 55%. However, if you could lower it down to 26% - 40% that's excellent.

To Reduce Email Bounce Rate:

1. Only Use Permission-Based (Opt-In) Email List.

2. Keep Your Subscribers' List Updated.

3. Don't Use Your First Campaign As A Way To 'Clean' Your List!

4. Verify The Email Addresses.

5. Be Consistent With Your Emails.

6. Write Quality Emails.

7. Avoid Creating Spam-Like Emails.

8. Do Not Use Free #Sender #Domains.

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Imagick php install


This article will guide you on how to install #Imagick #PHP #extension. Imagick is the most popular PHP extension which helps to create edit convert, and/or manipulates images. ImageMagick is a free and open source, feature-rich, text-based and cross-platform image manipulation tool used to create, edit, compose, or convert bitmap images. It runs on #Linux, #Windows, #Mac Os X, iOS, Android OS, and many other operating systems.

To use Imagick with PHP in your server, you can easily achieve it with the following #command:

sudo apt-get install php-imagick.

php -m | grep imagick.

sudo service apache2 restart.

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Duplicity restore full backup


This article will guide you on steps to perform a Duplicity-restore full backup. #Duplicity is an efficient #backup application.

#rsync is a protocol built for Unix-like systems that provides unbelievable versatility for backing up and synchronizing data. It can be used locally to back up files to different directories or can be configured to sync across the Internet to other #hosts.

Incremental Backup captures only the changes made since the last incremental backup. Saves both time and #storage space, and ensures that your backup is up to date. Differential Backup captures only the changes made since the last full backup, not since the last differential backup.

When a normal or full backup runs on a selected drive, all the files on that drive are backed up. This, of course, includes system files, application files, user data — everything. The downside of normal backups is that they take a very long time to run, and in some cases this is more time than a company can allow.

To Use Duplicity with GPG to Securely Automate #Backups on #Ubuntu:

1. Install the Prerequisite Packages.

2. Download and Install Duplicity from Source.

3. Create SSH Keys.

4. Create GPG Keys.

5. Run an Initial Test.

6. Create Your First Backup.

7. Restore a Backup.

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VestaCP mail not working How to fix


This article will guide you on different methods to resolve #Vestacp #mail #problems which generally occurs mainly due to #Exim problem, firewall issues, and so on. This tips will resolve the #email problems in VestaCP.

To fix email not working:

1. Verify your internet connection is working. If it's not, there are four things you can do to fix it.

2. Make sure you're using the correct email server settings.

3. Confirm your password is working.

4. Confirm you don't have a security conflict caused by your firewall or antivirus #software.

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How Chmod 777 works


This article will guide you on how to give #Chmod 777 to folders and files in #Linux. We also discussed the risks and more information about file permissions. 

If you are managing a Linux system, it is crucial to know how the Linux #permissions work.

You should never set 777 (rwxrwxrwx) permissions #files and #directories permissions. 777 means that anyone can do anything with those files.

To Give Root Privileges to a User in Linux:

1. Adding to Root Group using usermod. Let see how we can grant normal user root access by adding to root group.

2. Adding to #Root Group using Useradd Command.

3. Editing /etc/passwd file.

4. Setting as Sudo User.

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Vim Show Line Numbers in Linux


This article will guide you on how to show line numbers in #Vim. You can ask #nano to temporarily turn on line numbers by pressing Alt-C (meaning “Hold down the Alt key and the C key simultaneously”). This will show line and column numbers near the bottom of nano's window.

To Turn on absolute line numbering by default in vim:

1. Open vim configuration file ~/.vimrc.

2. Append set number.

3. Press the Esc key.

4. To save the config file, type :w and hit Enter key.

5. You can temporarily disable the absolute line numbers within vim session, type:/> :set nonumber.


Use the “:set number” command if you want to enable absolute line numbers; or “:set relativenumber” for relative Vi numbers.

If you want to turn off the line numbering, remember the command “set nonumber.”

When you have both absolute and, hybrid numbers enabled, you’ll have access to the hybrid mode!

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Laravel Contact Form to Send Emails with SendGrid


This article will guide you on steps to follow to create a #Laravel contact form to send #emails with the help of SendGrid.

#SendGrid manages all of the technical details, from scaling the infrastructure to #ISP outreach and reputation monitoring to whitelist services and real time analytics.

To integrate with SendGrid's #SMTP #API:

1. Create an API Key with at least "Mail" permissions.

2. Set the server #host in your email client or application to smtp.sendgrid.net.

3. Set your username to apikey.

4. Set your password to the API key generated in step 1.

5. Set the #port to 587.

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Restore a database in Alwayson Availability Group


This article will guide you on steps to restore a #database in alwayson availability group.

If you receive an #error that the database is in use, try to set the user to single user mode: USE master; GO ALTER DATABASE Database_name SET SINGLE_USER WITH ROLLBACK IMMEDIATE; Then try the restore with #recovery command again. Also, make sure you are on the latest service pack or cumulative update.

Creating a #SQL #Server AlwaysOn Availability Group.

Open SQL Server Management Studio and connect to the SQL Server instance. Expand the AlwaysOn High Availability folder in the Object Explorer. Right-click on the Availability Groups folder and select the New Availability Group Wizard.

To Restore a Database in a SQL Server AlwaysOn Availability Group:

1. Make the secondary server from which the backups were taken the primary server.

2. Remove the database to be restored from the AlwaysOn Availability Group.

3. Restore the database.

4. Add the database back into the Always Availability Group.

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Database version or build from backup file


This article will guide you on how to determine the database #version or build from a #backup file.
To know what #SQL version a #database is:
The first is by using either Enterprise Manager or SQL Server Management Studio and right clicking on the instance name and selecting Properties. In the general section you will see information such as on the following screenshots. The "Product version" or "Version" gives you a number of the version that is installed.
In order to find the SQL Server version from a bak file:
1. Here is the output returned by the RESTORE HEADERONLY statement. Here you will see a DatabaseVersion column that contains the value.
2. That's how you find out from which version of SQL Server a given backup file came.

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Rsync from Linux to Windows share


This article will guide you on how to use #Rsync to transfer #files from #Linux to #Windows share.

cwRsync is an implementation of rsync for Windows. rsync uses a file transfer technology specified by the rsync algorithm, transferring only changed chunks of files over the network. #cwRsync can be used for remote file backup and synchronization from/to Windows systems.

Syntax of rsync #command:

1. -v, –verbose Verbose output.

2. -q, –quiet suppress message output.

3. -a, –archive archive files and directory while synchronizing ( -a equal to following options -rlptgoD).

4. -r, –recursive sync files and directories recursively.

5. -b, –backup take the backup during synchronization.

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HTTP Flood DDOS Attack How to Mitigate the attack


This article will guide you on how to recover from DDoS attacks. Basically, protecting the web server against #DDoS #attacks is important. You can apply these measures to mitigate the error from causing troubles.

DNS #flood is a type of Distributed Denial of Service (DDoS) attack in which the attacker targets one or more Domain Name System (#DNS) servers belonging to a given zone, attempting to hamper resolution of resource records of that zone and its sub-zones.

To prevent DDoS attacks:

1. Buy more bandwidth. 

2. Build redundancy into your infrastructure. 

3. Configure your network hardware against DDoS attacks. 

4. Deploy anti-DDoS hardware and #software #modules. 

5. Deploy a DDoS protection appliance. 

6. Protect your DNS servers.

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Smurf DDoS attack How to fix


In this article , you will learn the measures taken by our Support Experts to mitigate #Smurf #DDoS #attacks.
A Smurf attack is a form of a distributed denial of service (DDoS) attack that renders computer networks inoperable. The Smurf program accomplishes this by exploiting #vulnerabilities of the Internet Protocol (#IP) and Internet Control Message Protocols (#ICMP).
Smurf is a network layer distributed denial of service (DDoS) attack, named after the DDoS.Smurf malware that enables it execution.
1. DoS is one of the oldest forms of cyber extortion attack.
2. As the term indicates, distributed denial of service (DDoS) means it denies its service to a legitimate user.
3. Ping of death and teardrop attacks are examples of such attacks. Flooding: Sending too much data to the victim can also slow it down.

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Backup Active Directory Domain Controller


This article will guide you on how to #backup #active #directory domain controller.
A System State backup generally includes a copy of any installed device #drivers and related files, most of the Windows directory, the #Windows #Registry, the Active Directory configuration (where applicable) and system files under Windows File Protection.
In production it is best practice to have at least 2 domain controllers per domain. If you factor in each child domain and the other domains that could easily scale up fast if you have two in each one.
To Configure Windows Backup Users on a Domain Controller:
1. Expand Active Directory "Users > Computers > Users".
2. Right-click the appropriate user who will be performing backups and click Properties.
3. On the Member Of tab, click Add to add the Backup Operators group to the User.
4. Click OK.

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List installed software Linux


This article will guide you on different methods to #list all #software, the number of #packages available on the server along with the method to copy them and use them when we reinstall our operating system(#OS).
Yum automatically refreshes the list of packages, whilst with apt-get you must execute a command 'apt-get update' to get the fresh packages.
To list of installed programs in #Linux:
1. Aptitude-based distributions (#Ubuntu, #Debian, etc): dpkg -l.
2. RPM-based distributions (#Fedora, #RHEL, etc): rpm -qa.
3. pkg*-based distributions (#OpenBSD, #FreeBSD, etc): pkg_info.
4. Portage-based distributions (#Gentoo, etc): equery list or eix -I.
5. pacman-based distributions (Arch Linux, etc): pacman -Q.

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Add Glance Cloud images to OpenStack


This article will guide you on steps to add #Glance #Cloud images to #OpenStack with different #Linux distributions which enables users to discover, register, and retrieve virtual machine images. 

After images are created they should be registered in Openstack Glance - #image operation service.

Upload Image Into Glance:

1. Replace <NAME> with the name that users will refer to the disk image by. 

2. Replace <IMAGE_FILE> with the local path to the image file to upload.

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WordPress Visual Editor White Text and Missing Buttons


This article will guide you on different methods to fix your #white #text and #missing #buttons in #WordPress visual editor problem. 

Classic Editor is an official plugin maintained by the WordPress team that restores the previous ("classic") WordPress #editor and the "Edit Post" screen. It makes it possible to use plugins that extend that screen, add old-style meta boxes, or otherwise depend on the previous editor.

Often, the absence of #TinyMCE #plugin in many WordPress #themes causes white text and missing buttons error in WP visual editor. 

To resolve it, you can simply go to Plugins and click on 'Add New' option. Now, search for the TinyMCE Advanced plugin in WP plugin store.

To enable visual editor in WordPress:

1. Log into your WordPress dashboard. On the left-hand side, go to Users > Your Profile. 

2. Check the box beside Disable the visual editor when writing.

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Plesk DNN install Service Unavailable error


This article will guide you on how to install DNN for our customers. In order to fix the Service Unavailable Error we should check whether the Dedicated application pool option is enabled in Plesk before DNN install.

A 503 Service Unavailable Error is an HTTP response status code indicating that a server is temporarily unable to handle the request. This may be due to the server being overloaded or down for maintenance.

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Install Graylog on CentOS 7 How to do it


This article will guide you on steps to #Graylog on #CentOS 7 and an effective method to make the logs more structured and searchable.

Graylog is a leading centralized log management solution built to open standards for capturing, storing, and enabling real-time analysis of terabytes of #machine data. 

Graylog is an open source log management platform which enables you to aggregate up to terabytes of log data, from multiple log sources, DCs, and geographies with the capability to scale horizontally in your data center, #cloud, or both.

To #Install Graylog 3 with Elasticsearch on CentOS 7:

1. Configure #SELinux. 

2. Add required #repositories 

3. Install #Java, #Elasticsearch, and #MongoDB. 

4. Configure Elasticsearch for Graylog. 

5. Install Graylog 3 on CentOS 7. 

6. Start Graylog service on CentOS 7.

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Backup and Restore Nagios Log Server


This article will guide you on the steps to perform #backup and #restore a #Nagios #Log #Server cluster. Taking Backup and Restore of Nagios Log Server helps not to lose any data as it is held in other instances.

Backup and recovery describes the process of creating and storing copies of #data that can be used to protect organizations against data loss. #Recovery from a backup typically involves restoring the data to the original location, or to an alternate location where it can be used in place of the lost or damaged data.

To do a backup and system restore:

1. Click Start.

2. Go to Control Panel.

3. Go to System and Security.

4. Click Backup and Restore.

5. At the Back up or restore your files screen, click Restore my files. 

6. Browse to locate the backup file. 

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Steps to Back Up And Restore Nagios System


This article will guide you on how to perform #Backup and #Restore of the #Nagios System are important aspects of the #administration and #maintenance of the #system. 

Backups are an important aspect of administration and maintenance of your system. They can easily facilitate the #migration of a Nagios XI #installation between a virtual server and physical server, and the design of a fail-over or #disaster #recovery instance of Nagios XI.

There are three main types of backup: full, incremental, and differential:

1. #Full backup. As the name suggests, this refers to the process of copying everything that is considered important and that must not be lost.

2. #Incremental backup. 

3. #Differential backup.

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Setting up OCSP stapling on Apache


This article will guide you on how to configure OCSP stapling on the Apache server.

To Check if #OCSP #stapling is enabled:

Go to https://www.digicert.com/help and in the Server Address box, type in your server address (i.e. www.ibmimedia.com). If OCSP stapling is enabled, under #SSL Certificate has not been revoked, to the right of OCSP Staple, it says Good.

To Configure your Apache server to use OCSP Stapling:

1. Edit your site's #VirtualHost SSL configuration. 

2. Add the following line INSIDE the <VirtualHost></VirtualHost> block: SSLUseStapling on. 

3. Check the configuration for errors with the Apache Control service. Apachectl -t.

4. Reload the Apache service. service apache2 reload.

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How to modify MSSQL Database Autogrowth Configuration


This article will guide you on how #MSSQL Database Autogrowth Configuration works. Therefore do not rely on the default #SQL Server Data and Log file Autogrowth value and must always set it to more realistic values depending upon the usage of the database.

To see data file growth in SQL #Server:

1. Connect to a SQL instance and right-click on a database for which we want to get details of Auto Growth and Shrink Events. 

2. It opens the disk usage report of the specified #database. 

3. In this #disk usage report, we get the details of the data file and log file space usage.

To Change default database location via SQL Server Management Studio:

i. Right Click on Server and Select "Properties".

ii. In the "Server Properties" dialog box, navigate to "Database Settings" tab and data/log files location under "Database default locations" group. 

iii. Click on "OK" to apply changes.

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Courier IMAP SSL How to secure your IMAP servers with SSL


This article will guide you on how to fix #IMAP #SSL #error which occurs as a result of incorrect file generation or wrong SSL #port #settings cause problems with the proper functioning of SSL on #courier IMAP SSL servers.

To add SSL support you have to install #OpenSSL or #GnuTLS before installing Courier-IMAP. #Download OpenSSL from http://www.openssl.org/, or GnuTLS from http://www.gnutls.org.

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Create a DigitalOcean Space and API Key


This article will guide you on the steps to create #DigitalOcean #Space and #API Key. You will also see the #server #URL, bucket name (or Space name), access key, and secret. With this information you can connect most any S3-compatible client or library to your new DigitalOcean Space!

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Remote Transport Pruning Failure How to troubleshoot


This article will guide you on steps to solve remote transport #pruning #failure in #cPanel which can occur when a directory has too much size, network #error, or due to the lowness of backup drive.

The remote transport process may time out if it tries to prune a very large directory. The following options can help you to solve this issue:

The transport may produce an error if it is unable to prune the directory due to its size. You can manually delete the directory from the remote backup location to troubleshoot this error.

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Restore Active Directory from backup


This article will guide you on how to restore active directory from backup. Back up Active Directory on a regular basis

You should back up your Active Directory regularly with an interval that doesn't exceed 60 days. #AD services presume that the age of the Active #Directory backup cannot be more than the lifetime of AD tombstone objects, which by default is 60 days.

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Last Restore Time of SQL server database


This article will guide you on how to collect #database restoration #history. The #SQL server database last restore time can be found using the system table in 'msdb'.
We get the following database #restoration history in my environment.
i. restore_date: It shows the database restoration #date.
ii. destination_database_name: We can get the destination database name using this #column.
iii. user_name: it gives user name that performed the restoration for that particular database.

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How to set up Amazon S3 through WHM


This article will guide you on how to configure Amazon S3 via WHM by accessing the 'Backup Configuration'.
To configure your #backups:
i. Login to #WHM and access "Backup Configuration >> Additional Destinations".
ii. Select #Amazon #S3 and click “Create new destination”.

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How to install Metricbeat on CentOS 7 to Gather Infrastructure Metrics


This article will guide you on the steps to install #Metricbeat and configure the Elastic Stack to collect and analyze system metrics. Metricbeat is configured using a #YAML configuration file. On Linux, this file is located at: /etc/metricbeat/metricbeat. yml. On #Docker, you will find it at: /usr/share/metricbeat/metricbeat.
Both #Filebeat and #Logstash can be used to send #logs from a file-based data source to a supported output destination.

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Method to Install Software From Source on Ubuntu


This article will guide you on steps to #install #software from #source on #Ubuntu. The Complete #command is apt-get which is the easiest way to install files/Softwares #packages.

Once installed, on the command line, you can use dpkg --listfiles packagename . For instance, dpkg --listfiles firefox . 

If you want to see what files a package contains without installing it, then you can install apt-file and use that.

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How to Secure Django Admin


This article will guide you on the methods to secure #Django admin. You can Deploy your site behind #HTTPS.

Best practices for keeping Django admin secure.

Something less sophisticated like a fake Django admin login screen page django-admin-honeypot.

It is always better for security to deploy your site behind HTTPS. Deploy your site behind HTTPS, it's easy to implement and it's free #Certbot, just choose #software and system and you're ready to go.


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Backup Outlook PST files


This article will guide you on how to perform #backup outlook PST files containing messages and all other Outlook data that is saved on the system which should be backup regularly.

#pst files created by using #Outlook 2010 are saved on your computer in the #Documents\Outlook Files folder. If you are using #Windows XP, these files are created in the My Documents\Outlook Files folder.

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QUIC flood DDoS attack


This article will guide you on how to prevent your #Servers from #QUIC #DDOS #Attacks which is capable of overwhelming a targeted server with unwanted #UDP packets. QUIC uses UDP, but a QUIC flood is not necessarily the same as a UDP flood.

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IIS Security for Sites Steps for server hardening


This article will guide you on the process to #secure sites in IIS to prevent site infections or defacing on a #Windows Server include poor file security or poor #configuration. 

In conclusion, the modular nature of #IIS allows for more granular control over web server resources and #security. However, this can either make your #web #applications more or less secure—depending on the person or group responsible for security.

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YUM History command Ways to use it


This article will guide you on #YUM history #command in #Linux which provides a detailed history of YUM #transactions in order to find out information about installed packages and those that where removed/erased from a #system. 

The yum history command allows users to review information about a timeline of Yum transactions, the dates and times they occurred, the number of packages affected, whether transactions succeeded or were aborted, and if the RPM #database was changed between transactions.

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304 not modified error Steps to fix it


An #HTTP 304 not modified status #code means that the website you're requesting hasn't been updated since the last time you accessed it.

Basically, your browser will save (or cache) web #pages so it doesn't have to repeatedly download the same information. This is an attempt to speed up page delivery. However, if this happens to your site, #visitors could be prevented from accessing your #web pages.

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Restrict anonymous login and ban IP address of attacker Windows


This article will guide you on the steps to Restrict anonymous login and ban #IP address of attacker by using Local Group Policy Editor in #Windows which allows us to prevent anonymous login and #IPBan helps to ban IP of #attacker. 

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Types of SQL server backups


This article will guide you on the different types of SQL Server backups and how to use them to run #SQL Server #backups to safeguard our #databases from user #errors, media failure, #hardware failure, and so on.

A full database backup backs up the whole database. This includes part of the #transaction #log so that the full database can be recovered after a full database backup is restored.

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Backup, Restore and Migrate a MongoDB database on CentOS 8


MongoDB is highly scalable, using shards. Horizontal scalability is a big plus in most #NoSQL databases. MongoDB is no exception. It is also highly reliable due to its replica sets, and the data is replicated in more nodes asynchronously.

This article will guide you on the steps to perform #backup, #restore and #migrate a #MongoDB #database on #CentOS 8.

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OpenStack instance Creation


This tutorial is all about assigning a fixed static IP address in OpenStack by creating ports and adding them to the instance.

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Search message tracking logs on Exchange 2016


This article will guide you on the different ways to search the message tracking logs by using the Get-MessageTrackingLog cmdlet in Exchange 2016.

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How to fix scheduled backups no longer working in Nagios


This article will guide you on how to solve Nagios scheduled backups failure which occurs when the database is currupted.

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Managing disconnected mailboxes in Exchange server


This article will guide you on how to manage disconnected mailboxes in Exchange Server. You should note that after deleting an Exchange mailbox or an Active Directory user account, it stores the mailbox in the mailbox database for some time.

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Openstack instance generating status error


This article will guide you on the best method of fixing Openstack instance generating status error caused by network issues or security issues.

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Solution to error VMWare virtual machine disks consolidation is needed


This article will help you to fix the warning error "VMWare: virtual machine disks consolidation is needed" experienced when trying to delete a snapshot, the snapshot VMDK files or logs have not been deleted correctly.

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How Yarn package manager works


In this article, we will install Yarn and consider different methods of managing Yarn package manager.

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PhpMyAdmin installation on Debian


This article will take you through the steps you need to take to install, Configure and Secure phpMyAdmin on your Debian 10 Server.

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Solve rsync error code 19


Best method of fixing Rsync error code 19.

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Method to change Vestacp admin password and fix vestacp errors


Changing VestaCP admin password could results in some errors due to bugs in the server environment. When an important Directory or missing file situation occurs, such errors tend to disrupt access to the Admin panel

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How to securely back up your Linux Ubuntu Centos and Debian Server


#Backup and #restore refers to technologies and practices for making periodic copies of data and applications to a separate, secondary device and then using those copies to recover the data and applications—and the business operations on which they depend in the event that the original data and applications are lost.

#rsync uses what is called a delta-transfer algorithm which compares files from source and destination and sends only the differences between them.


To automatically backup #files and directories in Linux:

1. archive the content. Backing up your files using tar is very simple using the following command: # tar -cvpzf /backup/backupfilename.tar.gz /data/directory.

2. create backup script. Now let's add tar command in a bash script to make this backup process automatic.


#Rsync, or Remote Sync, is a free command-line tool that lets you transfer files and directories to local and remote destinations. 

Rsync is used for mirroring, performing backups, or migrating data to other servers.

Backing up file systems means copying file systems to removable media (such as tape) to safeguard against loss, damage, or corruption. 

Restoring file systems means copying reasonably current backup files from removable media to a working directory.

Data losses can be a very frustration encounter for a server owner. To avoid such catastrophic situations in losing your website data, it is very important to do a regular backup for your server and website.

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