Link Swithover

prakashj · ‎10-15-2009

Hi,

I am facing an issue with GW redundancy using HSRP. When the active link goes down, the switchover to standby link takes less than 300ms. But when the active link comes back, there is a packet drop for more than 1 sec. It seems to be for return traffic and a mac learning issue. The link comes up and the forwarding plane is updated. Has anyone faced this issue before and was able to find a solution?

Rgds,

Prakash

dario.didio · ‎10-15-2009

Hi,

add a delay to your preempt command.

standby 1 preempt delay minimum 60

HTH,

Dario

prakashj · ‎10-15-2009

Hi Dario,

Thanks for your reply..

HSRP has no control on return traffic. right? The issue I am facing here is the route is installed in the routing table as soon as the active link comes up. But the mac-address-table is not updated. This leads to packet drop. Hence we tried adding a static arp entry. There was some improvement. But is it possible to delay the install of route in the routing table (static and connected routes) learned on that interface.

Regards,

Prakash