Error when setting up nrpe custom_check_mem

[MechanicalPopsicle]

I'm adding a service to existing host with currently working nrpe services. I can run the command locally on the host. When I try it remotely I get a couple different errors.
I tried running this manually from nagios server with multiple arguments including those on the KB article here https://support.nagios.com/kb/article/m ... s-774.html:

./check_nrpe -H x.x.x.x -t 30 -c custom_check_mem -a 'warn=free<20%' 'crit=free<10%'

Now I've tried this with multiple arguments and the "check_memory" command doesn't exist on the host nrpe client (but custom_check_mem does)

I get either "NRPE: Command 'custom_check_mem' not defined" or as with the exact command above "CHECK_NRPE: Receive header underflow - only 0 bytes received (4 expected)."

New to nagios - any help appreciated.

[scottwilkerson]

Can you show the custom_check_mem configuration line in the nrpe.cfg file on the remote system?

this error makes it look like it doesn't exist

I get either "NRPE: Command 'custom_check_mem' not defined"

Per the page you references

Nagios Plugins does not include a memory plugin however the linux-nrpe-agent does provide custom_check_mem. The thresholds for the plugin are triggered if the free memory is less than the supplied value.

Also, the command you are running is an example for checking memory on a Windows server with NSClient++

./check_nrpe -H x.x.x.x -t 30 -c custom_check_mem -a 'warn=free<20%' 'crit=free<10%'

[tgriep]

Even though the plugin is installed on the remote server, there has to be a command defined in the nrpe.cfg file so it knows what to run when a command come in to the agent.

Typically, this is the command that is defined in the NRPE agents config file.

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command[check_mem]=/usr/local/nagios/libexec/custom_check_mem -n $ARG1$

To test to see if the command is defined in the NRPE agents config files, try running the following example command from the Nagios server.

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./check_nrpe -H x.x.x.x -t 30 -c custom_check_mem -a '-w 20 -c 10'

If it passes, then there is noting that has to be done on the remote agent.
Just create a service check in nagios.

FYI, the above example is different from yours as the one you were trying is for a Windows system running NSClient++.


If the test fails, you will have to add the command to the NRPE agents config file.
Typically the config file for NRPE is /usr/local/nagios/etc/nrpe.cfg and you can edit it and add the following command to it.

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command[check_mem]=/usr/local/nagios/libexec/custom_check_mem -n $ARG1$

Save the change and restart NRPE and test it again from the Nagios server.

[MechanicalPopsicle]

That was it! - I definied it on the remote server in the nrpe.cfg file and not it is working. I told you I'm new:) lesson learned - thanks

[scottwilkerson]

That was it! - I definied it on the remote server in the nrpe.cfg file and not it is working. I told you I'm new:) lesson learned - thanks

Great!

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