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Design suggestions for a four 6500 layer 3 network?

Hi folks,

We've just purchased two 6509's with redundant sup720's and two 6506's with sup32's, and I need to configure them to replace our aging Extreme switches.

Two will be in the MDF on ground floor, and two in the IDF on second floor. All floors have their own VLAN and IP subnet, and there is a datacenter VLAN for servers, and a firewall VLAN acting as a glue network to the internet.

I'll use GigE channels for trunks between them in a fully meshed configuration.

My question concerns how to configure the VSI's on each switch. Each subnet has a default gateway, but how to virtualize this among the sup modules? It seems that HSRP, VRRP, and GLBP are available, with GLBP being preferred(correct me if I'm wrong).

Would I need to configure a separate VSI for each VLAN on each switch, then setup GLBP for all of them? Can this even be done?

Help please because I'm out of my depth on this one. Thanks for any responses,



Re: Design suggestions for a four 6500 layer 3 network?

The answer is yes just setup the same SVI for each vlan on both 720's and then setup hsrp or whatever you decide to use . In the case of hsrp you would then point all your nic clients gateways to the hsrp ip address . One side would be say and the other side would be , you could then set the hsrp ip address as , this would be your default gateway for all your clients in the subnet. Haven't dealt with vrrp or glbp .

New Member

Re: Design suggestions for a four 6500 layer 3 network?

Thanks for the help. HSRP would be fairly simple to setup I think (have used it for routers before) with only two layer 3 devices, but how about the two sup32's in the 6506's, which are also layer 3 capable?



Re: Design suggestions for a four 6500 layer 3 network?

Couple of options here:

1) You keep the Sup32's in the IDF Layer2 only, connecting with DOT1Q trunks to the 720s in the MDF. Only the 720s have the Layer3 SVIs.

2) You configure the Sup32s as Layer3, with 'no switchport' Layer3 links to the 720s in the MDF. Each Sup32 has an SVI for each VLANs on its switch.

Option 1 is your typical Campus Wide VLAN approach.

Option 2 is a Routed Campus Design.

Take a look at the attached document.

Hope this helps.

Please rate all helpful posts.