HSRP and L3 Switches

kwoodworth · ‎01-13-2012

Have 4 switches a mix of 3560 and 3550's in a test lab.

test-sv1 and test-sv2 connected via dot1q. Vlan 2 is setup on each switch with

test-sv1 as 192.168.31.2 and test-sv2 as 192.168.31.3 and a standby 1 ip 192.168.31.1.

test-sv3 and test-sv4 connected via dot1q. Vlan 10 is setup on each switch with

test-sv3 as 192.168.38.2 and test-sv4 as 192.168.38.3 and standby 1 ip 192.168.38.1

I connected test-sv1 and test-sv3 together with routed ports and test-sv2 and test-sv4 with

routed ports.

I have hosts on vlan 2 and hosts on vlan 10 on all 4 switches.. all hosts are reachable when things are fully

connected.

Problem comes up when testing things out.

When the active HSRP switch in a set is unplugged, the standby switch takes over. But the new active switch is

connected to the standby switch in the other set of 2 and all the hosts go unreachable because the standby switch

is in standby and won't pass any traffic.

Is there a way around this? Is this even a valid type of configuration? Would a routing protocol such as OSPF overcome

this? Should I change the routed ports to something else?

Thanks for any info.

glen.grant · ‎01-13-2012

You would need a L2 connection between your routing boxes carrying all active vlans. It would then go across that l2 crosslink to the active side router where it would get routed to the destination.