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More than 16 VLANs with HSRP on 3550

I have 6 C3550s running in HSRP configuration for about 40 VLANs. The HSRP groups that are assigned on those VLANs: 1- 16 (VLAN 1-16 = HSRP groups 1-16, VLAN 17 - 32 = HSRP groups 1-16 and so on). In normal condition the HSRP active HSRP peers are distributed among the 6 cores, so any core switch does not have more than 12 active HSRP groups. If on core fails the other one receives its HSRP peers and is going to have 24 active HSRP groups. Now if I try to ping every virtual IP (24 virtual HSRP IPs) 8 of them won't respond (only 16 virtual IPs replying). All the sh standby commnads and the syslog messgaes show that the switch has 24 active HSRP peer. For sure the sulution of reusing the HSRP groups to overcome the 16 active HSRP MACs limitation works on MSFCs but what about C3550s

The software on all 3550s: 12.1.9EA1c



Re: More than 16 VLANs with HSRP on 3550

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