Already set up my local net configuration to be monitored by Nagios3. I found a problem that Nagios3 reports a warning in the HTTP monitoring service of a Debian server set at ip 192.168.1.52, that has an individual virtual host and a mass virtual host for application development. I get this status message:

HTTP WARNING: HTTP/1.1 404 Not Found

I used the Nagios tools to check. servername is the name of the vhost server name I used in the Apache configuration.

/usr/lib/nagios/plugins/check_http -H servername -I 192.168.1.52

receiving this status message:

HTTP OK HTTP/1.1 200 OK - 37900 bytes in 0.504 seconds |time=0.503946s;;;0.000000 size=37900B;;;0

But when I check like this:

/usr/lib/nagios/plugins/check_http -I 192.168.1.52

I get the same status message as the warning, so I assume that I don't have Nagios completely well set up because doesn't recognize the vhosts for that server, how it should be as the check_http service shows.

Where should I look to fix that warning?