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unknown HSRP packet with native IOS on SUP720


I installed new 2 SUP720/6513 with native IOS 12.2(17b)SXA. As access switch I used C3550-48 with IOS 12.1(19)EA1a. This a configuration for an access-port:

interface FastEthernet0/1

switchport access vlan 1506

switchport mode access

switchport voice vlan 1505

no ip address

duplex full

speed 100

service-policy input VoIP-Trust-Pol

auto qos voip trust

no cdp enable

spanning-tree portfast

The HSRP is running on the distribution switches.

It seems to be that all running fine. Now I find some unknow HSRP paket with a sniffer.With debug standby I could see "redirect adv in" messages when the unknown HSRP packet appear. Have someone get the same symptom or can the unknown HSRP packet produce a critical problem?


Re: unknown HSRP packet with native IOS on SUP720

This unknown packets due to a new HSRP message type introduced in Cisco IOS 12.1(13)T. When other end router is Pre-12.1, then you can see in that router logs this error message "STANDBY-3-BADAUTH" because of it can understand only older HSRP format. Sniffer also trying to understand according to older HSRP format, so that it's giving UNKNOWN packet. This error won't effect HSRP normal operations. And to avoid these errors in your router logs, upgrade to 12.1(13)T and later.

Pls refer this bug for more details...