We have two 4507s at our core, running HSRP. We have three other 4507s at the edge, plus eight 2950s. All edge switches and WAN routers are connected to both core 4507s.
We have a Port-Group of two wires connecting the core switches together, and we built a VLAN interface (with an IP address) on each switch. This is L3 connection between the core switches.
We have NO direct trunk connecting the switches together, so there is no L2 connections directly between these two core switches. (The port-group mentioned above only operates on one VLAN)
I'm fighting all kind of STP and HSRP glitches, and I'm guessing that my connections between the core switches are partially to blame.
Bottom line: what is the preferred way to connect two core switch/routers?