Nagios Support Forum

I have just upgraded from Nagios 4.0.2 to 4.0.4 and when I try to change the status of some services I get the following error

Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator, root@localhost and inform them of the time the error occurred, and anything you might have done that may have caused the error.
More information about this error may be available in the server error log.

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Apache/2.2.15 (CentOS) Server at 192.168.17.120 Port 80

It is happening when I activate Service Commands, for instance changing the status of a service such as……

You are requesting to enable notifications for a service

The above error occurs after the [Commit] is done

The httpd error_log has the following message (example)
[Thu Apr 24 16:26:31 2014] [error] [client 192.168.17.156] Premature end of script headers: cmd.cgi, referer: http://192.168.17.120/nagios/cgi-bin/cm ... yp=6&host=................


I have had to revert back to Nagios 4.0.2 in the meantime

Can you run the following commands and show the output?

I have reverted back to 4.0.2 and operating OK

-bash-4.1# ll -d /usr/local/nagios/var/rw/
drwxrwsr-x 2 nagios nagios 4096 Apr 29 16:04 /usr/local/nagios/var/rw/
-bash-4.1# ll /usr/local/nagios/var/rw/
total 0
prw-rw---- 1 nagios nagios 0 Apr 29 16:05 nagios.cmd
srw-rw---- 1 nagios nagios 0 Apr 29 16:04 nagios.qh
-bash-4.1# sestatus
SELinux status: disabled
-bash-4.1#
cat /etc/redhat-release
CentOS release 6.3 (Final)

Have you tried 4.0.6? It was just released yesterday, I'll go look and see if this has been reported as a bug.

I have just installed 4.0.6 and it has the same problem...

From inside the nagios-4.0.6 source directory, I do
./configure
./make all
./make install

I have reverted back to 4.0.2 in the meantime.....

Did you run: as well?
If not, you may want to try to reinstall the newest version but make sure you run the command above or else your cgi will be built with different, older header includes and may not work.