Nexus 7010 ARP and COPP

[robert.horrigan]

Hellow Nexus Gurus,

I have had numerous instances where Broadcom NICs on Dell servers have started storming the LAN with directed ARP requests (unicast) for addresses off the subnet of the station sending the request.  I've had stations send 2GB of ARP requests to the 7K in under a minute in some cases.  Oddly this has not completely taken out the data center.  It has only caused weird temporary outages to some servers throughout various subnets.  I have no idea why the EDC wasnt taken out but I assume that many servers were saved due to the preconfigured COPP configuration.

class-map type control-plane match-any copp-system-class-redirect
  match redirect arp-inspect

Can anyone explain the behavior above as well as what that class-map does?

Does anyone have a solution to prevent these unicast ARP storms in the future?

Any insight would be much appreciated.

/r

Rob

[Surya ARBY]

enable storm control on unicast traffic on server ports

[robert.horrigan]

Well I only want to limit ARP though.

[vosm]

We are seeing issues with our Broadcom NIC, Dell, Hyper V servers with NIC teaming to seperate Nexus 2248's where random virtual servers will stop responding, sometimes the eventually start responding again sometimes we move them to a different chassis.  Is that the kind of "weird temporary outages" you were experiencing?  And how did you find the ARP storms?

Thanks