Nagios Web interface not working after upgrade

Are you facing Nagios web interface not loading?

This guide if for you.

Nagios web interface not loading error occurs after an upgrade or during installation.

Here at Ibmi Media, as part of our Server Management Services, we regularly help our Customers to fix Nagios related errors.

In this context, we shall look into steps to solve Nagios web interface not working error.

What triggers Nagios web interface not loading issue?

This error commonly occurs when we upgrade the Nagios and PHP is not updated in the server.

It can also occur if the web interface not configured properly.

If there is a problem with web server configuration Nagios GUI fails to load.

Different methods to fix Nagios web interface not loading issue?

To fix this error, apply any of the tips suggested below.

1. Update PHP version

This error commonly occurs when we upgrade to the newer version of Nagios. On upgrading to the latest version the requirement for the version needs to be met.

One of the major reason are the PHP version in the server is not up to date.

Thus, on checking the server found that the PHP was not up-to-date. Thus, we update the PHP to the latest version. Upgrading the PHP version in the server might affect the site running with a lower PHP version. If websites are running on the server.

2. Web interface not configured properly in Nagios

This can also occur after Nagios installation. In those cases, the web interface is not installed properly.

Thus, ensure that the web interface is installed in the server.

You can install the web interface using the command

sudo make install-webconf

Then we check the nagios.conf file is present in the Apache folder. In the Ubuntu server, the configuration file needs to be present in the sites-enabled folder. Thus, we found the file was not present in the location.

Thus, from the installation folder, we run the command to move the file to the correct location.

sudo /usr/bin/install -c -m 644 sample-config/httpd.conf /etc/apache2/sites-enabled/nagios.conf

Finally, we restart the Apache server using the command

service apache2 restart

After restarting the service the Nagios web interface starts to load.

3. Web server configuration in Nagios

The Nagios interface will fail to load if there is an issue with the webserver. Check the configuration using the command:

apachectl configtest

For Nginx server, we use the command;

nginx -t

From the output, the issue will be known and then we can resolve the error in the webserver and make the Nagios web interface to load.

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This article will guide you on how to fix #Nagios web interface not #loading #issue as well as its cause.

Before fixing, First, you need to make sure you have installed all required nagios #packages like nagios3, nagios3-core, and nagios3-cgi. Ensure you did not miss any required package.

If you are still not able to login, you can look at apache configuration and use htpasswd tool to add new username/password to be authorized. You need to find a file like /etc/nagios3/htpasswd.users. This may also be different on redhat. You can recreate the file or create another username/password.