We are using Nagios XI with Nagios Core 4.4.5. We have updated clients to nrpe 4.0.3 agent. We get "Remote does not support Version 3 Packets" messages in the server log. How to solve this, shouldn't nrpe 4.0.3 support version 3 packets by default. Is there something missing in the configuration? We know that requests can be configured to use version 2, only, but using the newest version is better, isn't it?
EDIT:
nagios-server:~$ /usr/local/nagios/bin/nagios -h
Nagios Core 4.4.5
Copyright (c) 2009-present Nagios Core Development Team and Community Contributors
Copyright (c) 1999-2009 Ethan Galstad
Last Modified: 2019-08-20
License: GPL
nagios-server:~$ cat /usr/local/nagiosxi/var/xiversion
full=5.6.7
major=5
minor=6.7
releasedate=2019-09-26
release=5607
Most likely you updated the NRPE client but did not update the plugins in the agent machine Run these commands to check some plugins versions (nrpe, http, ping):
/usr/lib/nagios/plugins/check_nrpe --version
/usr/lib/nagios/plugins/check_http --version
/usr/lib/nagios/plugins/check_ping --version
Also run this command to check the nrpe daemon version:
/usr/sbin/nrpe-ng --version
Most likely you would get reported version below 3 so you will need to update the plugins.