Using check_udp


Hi - has anyone successfully got check_udp working? I’m trying to use check_UDP (nagios-plugins 1.4.5) 1.80 but it keeps asking for a send/expect string and I’ve no idea what this is meant to be?

The target server is running syslog and the check so far has just been failing with this:

/opt/tools/libexec/check_udp -H -p 514
With UDP checks, a send/expect string must be specified.

So I guess my question is simply what should the following be set to:


Thanks - Julian.


try this: … 25450.html


Hi - yes, I should have said I’ve had a look around for this same problem and not found a great deal out. If I just pass some random string of text the check then times out.

/opt/tools/libexec/check_udp -H -p 514 -s ‘xyz’ -e ''
CRITICAL - Socket timeout after 10 seconds



no idea, just tried it quickly and it doesn’t work… i only use check_tcp at this time…


right …

well from what I can tell the general consensus is that check_udp is completely pointless as it doesn’t work.

Maybe I can figure it out.


sounds somehow strange… if it wouldn’t work it wouldn’t be in the plugins package… (at least i wouldn’t publish it :smiley: )

Should you find out anything please let us know :smiley:


rather than using check_UDP

you can use the UDP information in check snmp command and their OID

./check_snmp -H -C public -o udpInDatagrams.0 -w 100000 -c 105000 -r 1 -m RFC1213-MIB

Ammar Pakistan