Hello,
I'm getting a lot of WARNING/CRITICALs about ratio of "no tx credits" on
ports on Brocade switches. I suspect something is wrong in check_mk:
$ check_mk -n -v -p FC_SWITCH_HOSTNAME
....
Port 18 CRIT - assuming 2Gbit/s, In: 158.47KB/s, Out: 1.74MB/
s, no TX buffer credits: 90.51%(!!), Phy:inSync(6), Op:online(1),
Adm:online(1) (in=162273.698617;;;0;200000000
out=1822393.279242;;;0;200000000 rxframes=756.367023;;;;
txframes=1320.823425;;;; rxcrcs=0;;;; rxencoutframes=0;;;;
c3discards=0;;;; notxcredits=12604.370683;;;
....
And in the web interface (a bit later; so the numbers don't match
completely):
....
Service state: CRIT
Output of check plugin: CRIT - assuming 2Gbit/s, In: 228.34KB/s, Out:
950.65KB/s, no TX buffer credits: 96.31%CRIT, Phy:inSync(6), Op:online
(1), Adm:online(1)
Service performance data: in=233820.355617;;;0;200000000
out=973468.242159;;;0;200000000 rxframes=518.385831;;;;
txframes=753.48073;;;; rxcrcs=0;;;; rxencoutframes=0;;;; c3discards=0;;;;
notxcredits=19660.374087;;;;
Service check command: check_mk-brocade_fcport
....
Note from above output from check_mk:
rxframes = 756
txframes = +1321
···
----
sum of frames = 2077
====
notxcredits = 12604
If this is to make sense, the port would almost have an order of
magnitude more instances of no tx credits compared to transmitted/
received frames; that's weird. Such a port would certainly be in a bad
shape, if the numbers are to be believed, I think. But the switch's
administration interface doesn't have anything bad to say about the port.
Things connected to the port seem to work well. And when I manually
snmpwalk the device and look at rx/tx counters and no_tx_credits counts,
I only see ratios below 1%.
I have started looking at the code for brocade_fcport, but I must say I
have trouble seeing how the peculiar numbers are calculated.
At this point, we have 13 FC ports in state CRITICAL and 6 FC ports on a
handful of different Brocade FC switches in state WARNING because of "no
TX buffer credits"; if this were really true, I would expect a lot of
derived operational problems - which doesn't seem to be the case.
Does someone have comments about "no tx credits" and the brocade_fcport
check?
--
Regards,
Troels Arvin <troels@arvin.dk>
http://troels.arvin.dk/