Plugin time outs and DNS


Hi!, I was wondering if anyone using Nagios has experienced instances of NRPE timeouts when DNS goes down. We had a incident where one of our web servers starting shooting out tons of:

“CRITICAL - Plugin timed out while executing system call”

when one DNS server became unreachable. However, in our /etc/resolv.conf we have a secondary if the first goes down so I don’t know if NRPE has any logic to use secondary name server when primary name server goes down?



Is NRPE smart enough to know if goes down use

We are using NRPE Version: 2.8.1 on the server in question.



Use IP adresses



Can you be more specific? What do you mean use IP?



I meant that you use IP addresses in address variable of host definition…


I am monitoring 10 processes on remote server through check_by_ssh in nagios. 8 services works fine.
but in check_ping and check_ssh through ssh I am getting error "CRITICAL - Plugin timed out while executing system call"
These both works fine in command line… Only in nagios these have problem !!!

I tried by modifying “command_check_interval” = 180s (was -1) in nagios.cfg file…but didn’t work.
I tried by calling commands (check_ping and check_ssh through check_by_ssh) with option “-t 20” it didn’t work

how to resolve this? Does anyone have any idea?
please help …


Perhaps you can post what you have in your check_commands.cfg, and services.cfg for the check_by_ssh checks? If you are running check_ssh by hand and it works it sounds like there might be an error within the definition.


Is it possible to use dynamics dns for my server? I wish to apply a domain name. How do I fill up the field of Primary Nameserver and Secondary Nameserver? I plan to get a domain name, and use my server which is has no statis IP but plan to use a dynamics DNS. How should I set this up?