Category: Server Management Service

Clear Solaris Service Maintenance Status in Nagios - Troubleshoot and Resolve

This article covers how to fix Clear Solaris Service Maintenance Status Nagios issue. Basically, When the Nagios Core service finds an invalid configuration, the core service will not start. 

To fix the problem you must fix the problem Nagios Core is complaining about.

This is normal behavior of Nagios Core, it is not specific to Solaris.

However on Solaris, after a service has failed to start several times, Solaris will put the service into what is called a Maintenance State. This state prevents a small problem from becoming a bigger problem. 

Even after fixing the problem Nagios Core is complaining about, you must also clear the maintenance state on the service before Solaris allows a service to be started again.

This means that the service is in a maintenance state, however there is not a lot of detail as to the cause of the issue except that the Start method failed repeatedly. 

It does however provide the name of a log file /var/svc/log/application-nagios:default.log.

Execute the following command to perform further troubleshooting:

tail -20 /var/svc/log/application-nagios:default.log

To Clear Maintenance State on Nagios:

1. Run the following command to clear the maintenance state:

$ svcadm clear nagios

2. Execute the following command to start Nagios:

$ svcadm enable nagios

3. Now check the state of the service:

$ svcs -xv nagios

Failed to register iobroker in Nagios - Solved

This article covers how to resolve Nagios error, Failed to register iobroker. This problem can occur when custom operating system limits restrict the max number of processes that can be executed.

Custom limits are defined in the /etc/security/limits.conf file

You will need to increase the hard and soft values to resolve the problems you are experiencing, for example:

# harden against fork-bombs
*               hard    nproc           10000
*               soft    nproc           10000
root            hard    nproc           10000
root            soft    nproc           10000

 After making the changes it is recommended to reboot the operating system to ensure the limits are applied.

If the change does not fix the problem then you should increase the values again.

Secure osTicket with Lets Encrypt SSL Certificates - Do it Now

This article covers how secure osTicket with Let’s Encrypt SSL Certificates. You can use the Certbot to request for SSL certificates from Let's Encrypt Certificate Authority. The tool is not available by default and will need to be installed manually.

To Install certbot certificate generation tool:

1. Install certbot on Ubuntu /Debian:

# Install certbot on Ubuntu /Debian

$ sudo apt update

# Apache

$ sudo apt-get install python-certbot-apache

# Nginx

$ sudo apt-get install python-certbot-nginx

2. Install certbot on CentOS 8 / CentOS 7:

On a CentOS system run either of the following commands:

# CentOS 8

## For Apache

$ sudo yum -y install python3-certbot-apache

## For Nginx

$ sudo yum -y install python3-certbot-nginx

# CentOS 7

## For Apache

$ sudo yum -y install python2-certbot-apache

## For Nginx

$ sudo yum -y install python2-certbot-nginx

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.

DirectAdmin error Headers and client library minor version mismatch

This article covers how to resolve DirectAdmin: Headers and client library minor version mismatch error. Basically, this error can come up even after MySQL update and PHP rebuild via custombuild.

To resolve this error:

Perform a cleanup in custombuild and rebuild PHP

$ cd /usr/local/DirectAdmin/custombuild

$ ./build clean

$ ./build php n

Alternatively you can set it like this:

cd /usr/local/directadmin/custombuild

./build set php5_ver 5.3

./build set mysql 5.1

./build update

./build clean

./build apache d

./build php d

./build mysql d

To rebuild zend:

cd /usr/local/directadmin/custombuild

./build zend

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.