I have a 2800 with 2 Ethernet interfaces. I have a stack of 3750s (layer 2) connecting to the 2800. I would like to connect both 2800 Ethernet interfaces to the 3750 stack for redundancy. 1 connection can be active while the other is a standby or the connections can load share. How should I do this?
My first thought was HSRP. The router complains because the 2 NICs are on the same network.
I have considered IP unnumbered on the Ethernet interfaces and would create a loopback interface. I haven't tested this.
Additional information. I have 2 networks (voice and data). In my current set up, I use 1 Ethernet interface at the router which has been divided into sub-interfaces (1 data and 1 voice).
A 2800 with the necessary IOS can Etherchannel its two Ethernet ports. You should be able to make a cross stack member connection on the 3750s.