[Nagiosplug-help] check_ifstatus returning false timeout?

[Philipp Geschke]

Hello List,

I am experiencing a strange behavior of check_ifstatus.

Since a couple of weeks, check_ifstatus is reporting a couple of alarm
timeouts on 2 switches, which worked fine before.

First a assumed that there is something wrong with these switches, since
I can't think of a reason for check_ifstatus to work that strangely.

But now I started monitoring this a little closer, and it turned out,
that in fact check_ifoperstatus and a regular snmpwalk on these switches
work at the same time that check_ifstatus is reporting a timeout.

Has anyone ever experienced this kind of strange behavior? I still could
imagine that the nagios box' load is too high, but then other checks
should have strange results too. Plus, at the time manually checking, I
had a pretty low load:  load average: 0.05, 0.05, 0.12.

Here's a log of me manually triggering check_ifoperstatus,
check_ifstatus and snmpwalk directly one after another, and this is no
 coincidence:

nagios:/etc/nagios# /usr/local/nagios/libexec/check_ifoperstatus -k 46
-H switch2 -C secret
OK: Interface GigabitEthernet0/1/46 (index 46) is up.

nagios:/etc/nagios# /usr/local/nagios/libexec/check_ifstatus -C secret
-H switch2
ERROR: No snmp response from switch2 (alarm timeout)

nagios:/etc/nagios# snmpwalk -v1 -Of -c secret switch2
mib-2.interfaces.ifTable.ifEntry.ifOperStatus
.iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOperStatus.1
= INTEGER: up(1)
.iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOperStatus.2
= INTEGER: up(1)
.iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOperStatus.3
= INTEGER: up(1)
.iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOperStatus.4
= INTEGER: down(2)
.iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOperStatus.5
= INTEGER: up(1)
------ SNIP ------
.iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOperStatus.46
= INTEGER: up(1)
.iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOperStatus.47
= INTEGER: down(2)
.iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOperStatus.48
= INTEGER: up(1)
.iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOperStatus.257
= INTEGER: up(1)

I would appreciate any kind of hint here, even if it comes down to me
just being too dumb for nagios ;-)

Thanks a lot!

Regards,
Philipp