How to monitor Apache Tomcat in Nagios Core

[neworderfac33]

Good morning,

Once again encouraged by the expertise within this forum, I have another question.

My two test Windows clients use Apache Tomcat 7 to run the Jenkins continuous integration application.

I would like to be able to send email alerts if Apache is down, but I'm not certain if I can do this using a define service command within windows.cfg or if I need to install a plugin in order to do this?

Thanks in advance

Pete

[tgriep]

If you want to check that system to see if you can access the WEB interface, you cound use the check_http command from the Nagios system. That will let you know that the web server is up and that it is serving web pages.
If you need to check it to see if a certain port is open on that system, you could use the check_tcp command to do that.

Both of those commands should be already installed on your system.
If this isn't what you are looking for, post back with the details on how you need to monitor those systems and we can better help you.

[neworderfac33]

Thank you very much!

Can I utilise this from within my Windows.cfg file?

Pete

[tgriep]

Yes, you can add the service to your windows.cfg file.
Here is an example that you will have to edit for your system you want to monitor.

Code: Select all

define service {
  host_name                     www.google.com
  service_description           HTTP
  check_command               check_http! -f ok -I 74.125.228.212 -u "/" -p 80
  max_check_attempts            5
  check_interval                        5
  retry_interval                        1
  check_period                  24x7
  notification_interval         60
  notification_period           24x7
  contacts                      nagiosadmin
  register                      1
  }

[neworderfac33]

The application that I actually want to check for is Jenkins, which is installed on both the servers I want to monitor - it runs via a .WAR file, located within C:\program Files\Apache Software Foundation\Tomcat 7.0\WebApps\

So, I can either check that Jenkins is running, or that Apache is running as a service - if the latter isn't running, then the former won't be running either - whichever option is easier.

Also, please could you run through the syntax of the check_http command for me?

Regards

Pete

[hsmith]

The application that I actually want to check for is Jenkins, which is installed on both the servers I want to monitor - it runs via a .WAR file, located within C:\program Files\Apache Software Foundation\Tomcat 7.0\WebApps\

So, I can either check that Jenkins is running, or that Apache is running as a service - if the latter isn't running, then the former won't be running either - whichever option is easier.

Also, please could you run through the syntax of the check_http command for me?

Regards

Pete

If you're looking for all of the details of check_http you can get them by issuing this command:

Code: Select all

/usr/local/nagios/libexec/check_http -h

If this is not what you're looking for, please correct me.

[neworderfac33]

Still struggling, I'm afraid - the latest define service I have is:

Code: Select all

define service {
       use                      generic-service
       host_name                MYSERVERID
       #hostgroup_name           windows-servers
       service_description      Apache
       check_command            check_http! -p 443 -ssl
       }

but this returns:

HTTP CRITICAL - No data received from host

It isn't a "real" https in that the certificates are only internal ones, so the address bar shows the https part of the URL crossed out



Not sure where to go from here...

Cheers

Pete

[jdalrymple]

Code: Select all

       check_command            check_http! -p 443 -ssl

The -p isn't necessary and the -ssl should just be -S:

Code: Select all

[root@localhost etc]# ../libexec/check_http -I google.com -S
HTTP OK: HTTP/1.0 200 OK - 19432 bytes in 5.239 second response time |time=5.239068s;;;0.000000 size=19432B;;;0

[neworderfac33]

Thanks for your reply.
I'm running my Nagios on Redhat enterprise 6.6 and when I try to run your command, I get:

bash: ../libexec/check_http: No such file or directory

I have made the changes you suggested

Code: Select all

define service {
       use                      generic-service
       host_name                MYSERVERNAME
       #hostgroup_name           windows-servers
       service_description      Apache
       check_command            check_http! 443
       }

and the web interface returns
HTTP WARNING: HTTP/1.1 403 Forbidden - 1491 bytes in 0.002 second response time

If I add the -S parameter

Code: Select all

define service {
       use                      generic-service
       host_name                MYSERVERNAME
       #hostgroup_name           windows-servers
       service_description      Apache
       check_command            check_http! 443 -S
       }

the web interface returns
check_http: Invalid option - SSL is not available

HELP!

Pete

[neworderfac33]

Don't worry too much about this - I found another way to get around it, by monitoring the Apache Tomcat7 process instead.

Code: Select all

define service{
       use                      generic-service
       #host_name               MYFIRSTSERVER, MYSECONDSERVER
       hostgroup_name           windows-servers
       service_description      Service - Tomcat7
       check_command            check_nt!SERVICESTATE!-d SHOWALL -l Tomcat7
       }

Cheers

Pete