4500 dual core switch config issue

[nkariyawasam]

We have dual 4500 core swithces A and B. A is the active switch for all the VLANs. B is the standby.

At floor we have two 3550 stacks, A and B. These are stacked using Copper GBIC. Stack A is linkd with core A via fiber. Stack B goes to core B.

two stacks are interconected using a fiber.

FOr normall operation, all the traffic for bot 3550 stacks flowing though link A which directly goes to active switch. If the link A is broken, traffic flows though Link B.

Is there an way that we can utilize both Links ( A and B) in normal operation instead of one idling link ?

[ankurbhasin]

Hi,

So basically what you want is load balancing am I right?

If yes you can definetely do that. Can you confirm you have made 4500 switch A active and switch B standby via HSRP or STP.

Both ways you can make your switches active and standby , STP do it for layer 2 and HSRP for layer 3.

We can do load balancing which means using both the links both ways STP and also via HSRP.

Just confirm me your setup that which technology you are using to make your cat4500 swich A active and switch B standby and how many vlan you are having in your network.We can move forward then.

Will wait for your reply.

Ankur

[glen.grant]

Agree with ankur in using hsrp , in fact

I would alternate which side active in the hsrp setup depending on how many vlans you are routing thru these . Also whatever side is the active hsrp side set your spanning tree root for the vlan to that side . This load balances at layer 3 and also gets your spanning tree in the correct setup for this configuration . We have a huge setup like this on our 6500's with about 80 separate /24 subnets . Works well .

[ankurbhasin]

Hi,

As the original poster is having a dual core he must be having a seperate core and distribution and distribution layer must be taking care of HSRP and core must be taking care of STP primary and secondary roots. In case of collapse core it is recommended to have same switch to handle STP and HSRP load balancing and redundancy.

Just confirm what setup you are running?

Ankur

Please

[nkariyawasam]

I have two 4507R switches, as collapse distribution (CD).

Right now I have only one vlan defines. Later on there might be additional vlans. But customer wants to load balance even within the same vlan, via two uplinks.

The CD-A is made active for the VLAN by defining higher priority for the VLAN. Also the CD-A has been defined as STP root primary and the SD-B is the STP root secondary.

I know that if I have more VLANS I can make CD-Aactive for set of VLANs and the CD-B will be the active switch for the balance VLANS.

But here what I want is to load balance between two links within the same VLAN.