03-19-2010 05:27 AM - edited 03-06-2019 10:13 AM
We have 2 6513's to which the servers are dual connected in a Failover mode. This is a single Vlan (vlan1) with about 100 physical servers. The 2 switches are connected to the core 6509's via 2port etherchannel running at Layer 3, and there is an 8gb Etherchannel between the 2 switches.
What I am seeing at the packet capture box is that the server will appear to have 2 mac addresses. 1 being the maac in the server and the second being the VLAN 1 interface MAC Address. This seems to happen to packets on the A switch going to the B switch. B is the Active device in HSRP and A is the Standby. We are not sure what we are looking at. It appears that in some cases the TTL has been decremented as if it has gone past a router. The Switches do run EIGRP and the VLAN 1 interfaces are in the network staements. We are thinking "Local Router Problem" but I can't find any documents that discusses this. Any conversation or direction will be appreciated.
03-19-2010 06:03 AM
Hello Bill,
if the TTL is decremented the packet is routed and the source MAC address has to be that of one switch as seen on the other one.
This is strange it should not happen unless switch1 loses connectivity to vlan1 (no ports in Vlan1 in STP forwarding state but this is not possible)
Hope to help
Giuseppe
03-19-2010 06:08 AM
Bill,
On the server side are you NIC teaming?
Also is the SVI for vlan 1 on the 6513 or 6509?
Reza
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