Unable to remove host from hostgroup

[sal@coned]

Using: Nagios XI 2011R1.6

I have 2 hosts that belong to the same set of hostgroups,
the hosts are joined to the groups by going into the host config and selecting the hostgroup

The problem is that I can delete hostgroups from one host and not the other ( this only happens with a specific set of hostgroups ).

Where do I begin trouble shooting this issue?

=======================================================================
The log error:
'/usr/local/nagios/etc/services/win_system.cfg'...
Error: Could not expand hostgroups and/or hosts specified in service (config file '/usr/local/nagios/etc/services/win_system.cfg', starting on line 136)
Error processing object config files!


***> One or more problems was encountered while processing the config files...

Check your configuration file(s) to ensure that they contain valid
directives and data defintions. If you are upgrading from a previous
version of Nagios, you should be aware that some variables/definitions
may have been removed or modified in this version. Make sure to read
the HTML documentation regarding the config files, as well as the
'Whats New' section to find out what has changed.

[nscott]

A good place to start with that problem would be to look in that config file (located at /usr/local/nagios/etc/services/win_system.cfg) and goto line 136. Generally the line numbers will get you in the right area, so check the host and hostgroup that is defined inside the service and make sure they both exist.

[sal@coned]

The config files look correct, the service references a hostgroup.
The host group exists and has no hosts directly configured.
The host file referencec the hostgroup.

Can the data base be quried for corrupt data?

[sal@coned]

I performed a siple test by adding a host to the hostgroup via the hostgroup config window.
I saved and applied the changes succesfully,
However when I reversed the procedure and deleted the host from the hostgroup via the hostgroup config window I saved the config and the apply failed.

No other changes were made between these two steps.

[sal@coned]

I found the cause for the error.

You cannot have an empty hostgroup.

[sal@coned]

I have a question re: hostgroups.

The way we normally work is that the nagios engr creates the services and hostgroups, then the server admin adds servers to the groups.

Is it normal for the system to fail if a hostgroup is empty ?
Is there any discussion about chnaging this behavior ?

It would be extremely helpful if the service refrencec a hostgroup and have that service be active only if the hostgroup has members in it.
Rather then failing.

Thanks
Sal

[nscott]

Yes, generally hostgroups must have members. There is a great mailing-list thread on the topic located here:

http://www.mail-archive.com/nagios-user ... 06710.html