Nagios Core is a free to use open-source application for performing monitoring of systems, networks and infrastructure in general. 

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

In this context, we shall look into the main causes of the error and how to get rid of it.

What triggers Nagios error while trying to delete host?

Basically to delete a host on Nagios Core "Nagios XI", you can select the delete icon within the Host Management page. TO do this navigate through "Configure >> Core Config Manager >> Services (delete all host’s dependencies) >> Hosts >> Delete host".

In a few cases, when trying to delete or deactivate a host from Nagios Core Manager you can experience error that shows that the host item cannot not deleted.

How to solve Nagios error while trying to delete host?

To fix this error, simply follow the steps given below;

i. To delete or deactivate a host, try to delete or deactivate all of the services and other objects attached to it.

ii. For instance if you use services, start by clicking the Services link located in the left-hand navigation pane of the Core Configuration Manager.

iii. Next, with the search bar look for the services attached to the host you want to delete.

iv. By default, they are named after the host, so you should search for the hostname.

v. In some cases, if you created it manually, they will not be named after the host. Then you can search them by their given names as specified in the error report.

vi. As soon as you detect the attached services, then delete or deactivate it. To do it, check their individual checkboxes. These checkboxes are located to the left of their entries in the search results table.

vii. Next, select or deselect all the displayed services. For that, you can check or uncheck the box to the left of the words "Config Name" at the top of the table.

viii. After selecting the desired services, use the "With Checked" dropdown box located beneath the search results table to choose the desired action.

ix. Now, select the Delete option to remove the services from the Core Configuration Manager database. Deactivation will only deactivate and make them inactive. So deactivated hosts can be reactivated at a future time when you need to use them again.

Once we delete or deactivate the services, we go back to the host and delete or deactivate it as well if necessary.

[Need support in fixing Nagios errors?  We are available to here you today.]