Nagios Support Forum

Hello all,

I am setting up check_nrpe to query a bunch of servers that all have IPv6 addresses. All machines have NRPE 3.2.1 (and the server has that same version of check_nrpe.

When I run a test:
I get the following error:
The reason for the connection failure is very simple - that IPv6 address is not the address of the machine I am trying to connect to.

All other programs on the Nagios host correctly resolve the IP of the other server. For example, dig AAAA myhost.example.com, host myhost.example.com, ping6 myhost.example.com, and others all get the correct address. Only check_nrpe gets it wrong.

The interesting thing is that the first half of the address is correct. Only the last half is totally messed up. (My boss does not want me to share the IP addresses publicly, but I can PM them if you want.)

If it makes a difference, the Nagios host is on Linode and the NRPE machines are all on AWS EC2.

@kohenkatz Hi Kohenkatz! Could you submit here or pm to me your nrpe.cfg file. It should be located in

/usr/local/nagios/etc/nrpe.cfg

Also, can you upload the plugin as well so we could test it?

Hello,

It turns out that the issue is not actually as I originally described.

The actual problem for me was that the firewall was still blocking the IPv6 traffic on port 5666.

The fact that the IP address is displayed incorrectly in the output of check_nrpe was a red herring. The whole time it was actually trying to connect to the correct IP address but just displaying the IP address wrong in the error message.

So the next question is this: Should I file a bug report on NRPE on GitHub?

npolovenko wrote:Also, can you upload the plugin as well so we could test it?

The plugin is this one: https://github.com/yakatz/nagios-plugin ... restart.py

Glad it sounds like this is solved.

kohenkatz wrote:So the next question is this: Should I file a bug report on NRPE on GitHub?

This doesn't sound like a bug, because NRPE doesn't configure your firewall so there wouldn't be anything to fix.

kohenkatz wrote:

npolovenko wrote:Also, can you upload the plugin as well so we could test it?

The plugin is this one: https://github.com/yakatz/nagios-plugin ... restart.py

I don't believe this will be necessary since the issue was the firewall

@scottwilkerson The bug I meant is about the fact that check_nrpe's error message displays the wrong IP address.

Reported https://github.com/NagiosEnterprises/nrpe/issues/168

kohenkatz wrote:Reported https://github.com/NagiosEnterprises/nrpe/issues/168

nice find.

kohenkatz wrote:Reported https://github.com/NagiosEnterprises/nrpe/issues/168

Oh, got it! Thanks.