I have a customer who recently replaced their (2) Cisco 2600 routers configured in an HSRP with (2) ISP links in an ethernet hand off Active/Standby with (2) Cisco 3750 stacked switches.
Interface vlan 2201
ip address 208.68.38.113 28
interface gigabit 1/0/1----------------connected to Primary ISP Link
switch port access vlan 2201
no spanning-tree
interface gigabit 2/0/1--------------- Connected to Secondary ISP Link
switch port access vlan 2201
no spanning-tree
Two things I had to do in order for above configuration to work.
disconnected secondary ISP link otherwise the switch would report an error "Same IP address 208.68.38.113 detected" and disable stp on ports.
I think the only way to configure the above scenario is to undo stacking between both swtiches and configure HSRP for dynamic failover.
Why did I had to disable STP on ports? I was not able to ping the ISP routers until I dsiabled the STP on two ports
