RE_Woods's questions

I run a Nagios Core server on a LAN. I have 5 windows machines outside the network I am talking to via five ssh tunnels on 5 different ports listening to five custom NSClient++ apps. All is working well with this configuration, however I am noticing that check_nt MEMUSE is giving us odd numbers, when in fact all we want/need is the actual Physical memory.

After much digging I discovered check_nrpe, which look like it will give me the data I'm looking for.

I put the following in the commands.cfg:

define command {
       command_name    CheckWindowsPhysicalMem
       command_line    $USER1$/check_nrpe -H $HOSTADDRESS$ -p 5666 -c CheckMEM -a MaxWarn=$ARG1$% MaxCrit=$ARG2$% ShowAll=long type=physical
}

And I put the following in my windows.cfg

define service{
        use                     generic-service
        host_name               HOSTNAME
        service_description     Physical Memory
        check_command           CheckWindowsPhysicalMem!80!90
}

I restarted both nagios and nagios-nrpe-server, and now I'm getting this error:

CHECK_NRPE: Receive header underflow - only 0 bytes received (4 expected)

I am not sure what I missed here, but if seems like a dependency or a package. Google-fu lost on this one.

The default port for NSClient++ is 12489. Is is possible to change this port, and if so where does this change need to be made?

I have installed freeSSHD on my Windows machine, created a user, enabled tunneling, copied over a public rsa key, and installed NSClient++. On my Nagios server, I have Nagios running and a Windows.cfg file that looks correct.

I am able to ssh from the nagios box to the windows box with the following:

ssh user@windows-box-ipaddr

and

ssh -f -N -L 127.0.0.1:1433:windows-box-ipaddr:1433 administrator@windows-box-ipaddr

Despite this, I'm seeing errors such as these in Nagios:

connect to address 127.0.0.1 and port 12489: Connection refused

I am not sure what IP address needs to go in the windows.cfg for the define host, nor am I sure what the NSClient++ IP should be set to.

What I do know for certain is that I can get this servers to connect through SSH. I am thinking that I should be using another port or perhaps I need to open many ports in the firewall. At this point I am at a standstill.

I am running Nagios from my LAN on a VM running Ubuntu Server. I am trying to monitor a Windows server located and via the Internet. I set up a public IP in my NAT which forwards to my Nagios server as needed.

I cannot seem to be able to ping the Nagios server from the Windows server, nor can I reach the Windows server from the Nagios server (can only ping the Windows server if I disable the public profile in the Windows Firewall).

I'm not sure where/how to proceed. I read that ports 5666-5667, 1248-1249 and 12489 need to be forwarded, but I do not know if that would be on the Nagios server, Windows Server or all of the above.