I came across some weird behavior (I think) in Junos recently. Nothing major, but an annoyance nonetheless.
Juniper EX4550
Let’s check out some statistics on this beautiful looking EX4550 stack, shall we?
john@EX4550> show pfe statistics bridge
Slot 0
PFE: 0
----------------------------------------
---- Ingress Counters ----
-- Set0 --
Received: 654383803
VLAN Filtered: 0
Security Filtered: 0
Other Discards: 324
-- Set1 --
Received: 654383797
VLAN Filtered: 0
Security Filtered: 0
Other Discards: 324
[...]
Oh dear look, 324 “Other” discards on my EX4550. I sure hope they aren’t incrementing. Let’s issue the command again and check if the 324 figure has increased?
{master:0}
john@EX4550> show pfe statistics bridge
Slot 0
PFE: 0
----------------------------------------
---- Ingress Counters ----
-- Set0 --
Received: 913272
VLAN Filtered: 0
Security Filtered: 0
Other Discards: 0
-- Set1 --
Received: 913267
VLAN Filtered: 0
Security Filtered: 0
Other Discards: 0
[...]
No it hasn’t. In fact it has mysteriously reset itself along with all the other PFE statistics. That is, well, suboptimal to say the least.
It’s probably a known bug, though it’s not important enough for me to go look it up. Maybe it’s even intentional (though for the life of me I can’t figure out why you’d want that behavior). Still, it’s something to be aware of. For reference, here’s the code version I’m using:
john@EX4550's password:
--- JUNOS 12.2R4.5 built 2013-04-04 11:26:24 UTC
{master:0}
john@EX4550> show version
fpc0:
--------------------------------------
Hostname: EX4550
Model: ex4550-32f
JUNOS Base OS boot [12.2R4.5]
JUNOS Base OS Software Suite [12.2R4.5]
[...]
Happy troubleshooting.
You’re not supposed to be using JUNOS 12.2 anyway since it’s beyond its EOL date: http://www.juniper.net/support/eol/junos.html
Agreed, but sometimes we don’t get to pick the environment in which we have to operate.
As far as I can tell the “ingress – other discards” is packets which should not be forwarded. Mainly BPDUs without a listening process on the switch (eg, LLDP packets are present, but there is no “protocols lldp” configuration).
As for the counters not being monotonically increasing — bleh.