null ARP table on a C5 stack

[Omar_Valente]

I have a stack composed of 2 C5 series with F/W Fw:06.71.03.0025

It's some day that I'm experiencing networks problems (hosts becoming unreachable and getting back online after a random time)

The only strange thing that I've noticed is that the "show arp" command returns null adrresses

C5(su)->show arp
LINK LEVEL ARP TABLE
IP Address Phys Address Flags Interface
---------------------------------------------------------
10.104.2.14 00-00-00-00-00-00 host
10.101.2.226 00-00-00-00-00-00 host
10.101.2.241 00-00-00-00-00-00 host
10.101.3.92 00-00-00-00-00-00 host
10.101.50.5 00-00-00-00-00-00 host
10.103.2.134 00-00-00-00-00-00 host
10.103.10.11 00-00-00-00-00-00 host
---------------------------------------------------------

Any idea on what caused/how to fix this ?

Thank you

Omar Valente

[Frank11]

Thx for that. Not sure if this is related. My switch does do routing. Under the routing interface I see the ARP table populated as per normal but the switch ARP table I get null values like yourself.

My question is - does the switch ARP table affect the routing ARP table?

[Omar_Valente]

long story short. My issue was with some card readers with non standard behaviour on the net. these devices somehow were getting flushed from the switch mac address table but were still present on the ARP table (and since they were on the arp table no flood was taken to find them). Lowering the ARP table agetime to value much smaller than the switch SAT table solved the problem

Omar Valente

[Frank11]

Any update for this. Getting the same issue.

[Omar_Valente]

Yes it is

[Jason3]

Is the switch routing?