Best way to configure redundant interfaces on a router

[CiscoPurpleBelt]

Let's say you have 2 routers for redundancy connected to 2 switches for redundancy (so each switch connects to each router). If I need the same sub-interfaces on each interface on the router since they are providing redundant connections for each switch as well as doing routing for certain subnets, I would  have to configure IRB with the same BVI assigned to each redundant interface on the router correct? Is there another way to do this?

[Francesco Molino]

Hi

Not sure i got your design.
Are the switches connected together?
Routers are doing routing for all vlans? And default gateway?

If you have sub interfaces for all your vlans on both routers and acting as default gateway for these vlans, why not simply doing hsrp or glbp for redundancy?
Or maybe i missed something, in that case can you attach a quick drawing?

[CiscoPurpleBelt]

See drawing - sorry I don't have VISIO on this PC right now.

Yes the 2 switches can be.

Yes could do HSRP between both swithces for inter-vlan routing, but how about if you wanted both routers just to be the DG for both switches, say the internal int face for each switch connection to be 10.1.1.1? As you know I can't put same IP without overlapping. So is IRB one way to do it or what is best way it should be done?

[Francesco Molino · Accepted solution]

Gotcha.
Yeah irb bvi would be the way to go and you can also do hsrp in addition to have the vip as default gateway.

The config would look like: (you can add hsrp on bvi)

bridge irb
!
interface Fa0/0
no ip address
bridge-group 1
!
interface Fa0/1
no ip address
bridge-group 1
!
interface BVI1
ip address 192.168.1.1 255.255.255.0
!
bridge 1 protocol ieee
!
bridge 1 route ip
!
ip route 0.0.0.0 0.0.0.0 192.168.1.2

[CiscoPurpleBelt]

Awesome! So I would put my HSRP configs under the BVI interface?

[Francesco Molino]

Yes you can add hsrp to your bvi interface