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Possible to Load balance across 2 IRB links?

Level 1
Level 1

Good Day All,

I would like to find out if is it possible to load balance across the following setup.

From Site A to B, there are 1 pair of routers at each site, total of 4 routers.

There are 2 x layer 2 link between Site A & B

Site A                                                 Site B

Router A1-----------------link1---------------Router B1

Router A2-----------------link2---------------Router B2

Due to server clustering, I need to stretch the VLANs over the 2 sites with Integrated Route Bridging (Just read up on this, and not sure how it works yet)

I am exploring the option to let the "odd" vlan through link 1, and "even" VLAN through link 2.


To achieve load-balancing as close to 50/50 as possible.

Is the above setup possible?

  •      Using IRB to stretch the VLAN?
  •      Using the Odd/Even VLAN to Load Blanace?

Are there any other methods to achieve this?

3 Replies 3

Reza Sharifi
Hall of Fame
Hall of Fame

How are each cluster connected to the routers? Is there a Switch sitting behind each set of routers?
What type routers are these ?
You would have to use IRB and put the interface connected to router and the interface between the routers on the same subnet using BVI


Sent from Cisco Technical Support iPhone App

Good Day,

The routers model are c2901.

There is a stack of 3750 switches behimd the routers at each sites.

The cluster servers is connected to the switches.

For IRB, if i have to extend multiple VLAN, so I have to create a BVI for each VLAN?

Or a subinterface on the BVI for each VLAN?


If you have a stack of 3750 switches in each location, than just connect the switches together and extend the vlans across both locations.  No need to use the routers.


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