Nagios Support Forum

This is fixed by adding define command { command_name check_nrpe_v2 command_line $USER1$/check_nrpe -H $HOSTADDRESS$ -c $ARG1$ -t 50 } in /etc/nagios/objects/commands.cfg file and creating new cfg files in /etc/nagios/objects for upgraded vms and adding these new config files in /etc/nagios/nagios.cfg

Hi Emmett,

[root@prod-mon-n1 ~]# /usr/lib64/nagios/plugins/check_nrpe -H prod-nlog-n1
NRPE v4.1.2

[root@prod-mon-n1 ~]# /usr/lib64/nagios/plugins/check_nrpe -n -2 -H prod-nlog-n1
CHECK_NRPE: Receive header underflow - only -1 bytes received (4 expected).
[root@prod-mon-n1 ~]#

After rhel8 to rhel9 update, nagios client is not connecting. Message on ui is:
CHECK_NRPE: Receive header underflow - only -1 bytes received (4 expected

This is now working with the latest rpm update

Nagios core GUI/UI fails to open after nagios-4.4.6-4 to 4.4.9-1 update on Rhel8 vm. Whoops! Error: Could not read host and service status information! Nothing in /var/log/nagios/nagios.log. /sbin/nagios -v /etc/nagios/nagios.cfg doesn't report any errors. cgi.cfg exist in the same directory as nagi...