Arpmgr busy, Possible ARP flood messeges on ACE

[gavin han]

Hi, we keep on getting following msg on ACE logging in Admin context. we have in total 5 context including admin context?

Nov 18 2012 07:54:08 : %ACE-2-901001 kernel:  Arpmgr busy, Possible ARP flood, 22996 arp pkts were dropped over las

t60 secs

what could be the problem? we get such msgs every 2-3 mins.

ace/Admin#  sh processes cpu | i arp

1956      10536631   8246809   1277      0   0.0 %   0.0 %   0.3 %  arp_mgr

1971        872158  14343950     60    0.0   0.0 %   0.0 %   0.0 %  arp_mgr

1972        299330   5876080     50    0.0   0.0 %   0.0 %   0.0 %  arp_mgr

I found one post with similar issues as per following link. we don't have any server NICs configured in active/active mode:

http://forum.broadcom.com/showthread.php?512-ARP-flooding-caused-by-BACS3-and-5709C-NICs-bringing-down-Production-network/page2

[Nicolas Fournier]

Hi Gavin,

For now the only way to see where the arp storm is coming is to get a span of the VLANs going to the admin context.

To do so, if you have a module:

https://supportforums.cisco.com/docs/DOC-15652

An enhancement request has been opened to list the arp top talkers but unfortunately, it is not implemented yet:

CSCub45617 Implement top ARPers output to identify ARP flood source.

Regards,

Nicolas

[gavin han]

Hi Nicolas, I had TAC case open. we spanned vlans and took capture but we didn't see any arp storm so TAC has no idea of what's going on. could you provide any suggestion please.

[Nicolas Fournier]

Hi Gavin,

Can you let me know your SR#?

Regards,

Nicolas