Solved: 6509 Upgrade

jeffreydorn · ‎02-17-2009

I need to upgrade our 2 core switches. We have 2 existing 6509 with Supervisor 1A cards. They run IOS on the route processor side and CatOS on the switch side.

We've purchased 2 6509 with the sup720. I have enough space that I have them racked right next to our existing 6509s. I have the 2 setup as a VSS pair, and now I'm wondering where to go from here.

Is there a best practice on how to perform an upgrade like this? Do I configure these new switches exactly like the old ones and then do a major switchover all in one night? Any other suggestions?

Giuseppe Larosa · ‎02-17-2009

Hello Jeffrey,

by having setup a VSS pair you have already done something different.

You can insert the new device in the network with higher STP priority.

As usual takes care of VTP parameters to avoid problems with revision numbers.

phase a: connection to the two current core switches with STP parameters that make it not the root bridge.

make one current core switch the root bridge for all vlans

configure the VSS to be a VTP server in the right VTP domain

phase b: you move the backup uplink of each access switch to the new VSS pair.

(this can be done if you have the same root bridge for all vlans)

you need also to migrate a link to wan routers to the VSS

phase c:

make the new VSS the root bridge for all vlans

phase D : migrate to VSS the second uplink of each access layer switch.

This can be a way to handle the migration

e) if everything is working fine you can power off the old core switches

Hope to help

Giuseppe

View solution in original post

Giuseppe Larosa · ‎02-17-2009

Hello Jeffrey,

by having setup a VSS pair you have already done something different.

You can insert the new device in the network with higher STP priority.

As usual takes care of VTP parameters to avoid problems with revision numbers.

phase a: connection to the two current core switches with STP parameters that make it not the root bridge.

make one current core switch the root bridge for all vlans

configure the VSS to be a VTP server in the right VTP domain

phase b: you move the backup uplink of each access switch to the new VSS pair.

(this can be done if you have the same root bridge for all vlans)

you need also to migrate a link to wan routers to the VSS

phase c:

make the new VSS the root bridge for all vlans

phase D : migrate to VSS the second uplink of each access layer switch.

This can be a way to handle the migration

e) if everything is working fine you can power off the old core switches

Hope to help

Giuseppe

jeffreydorn · ‎02-18-2009

Thanks, that helps a lot. When should I be setting up the layer 3 addressing for the VLANs? I want to use the same IPs for the cores and the VLANS, so how can I seamlessly program them without downtime?

Thanks again in advance.

Giuseppe Larosa · ‎02-19-2009

Hello Jeffrey,

if you are using HSRP on the client Vlans you can actually give to the SVIs ip addresses that are different then the old core switches.

Then after having given to VSS root bridge role you can also provide an higher HSRP priority to the VSS so that it serves users in the client Vlans.

About backbone links: if you are using dynamic routing in any form and subnet size allows it you can use different IP address on the VSS the routing protocol will accept this.

If you are using static routes you need to use the same ip addresses that are used as next-hops on the neighbors. In this case you need to shut the SVIs on old core switches and to enable the exact copy on VSS.

Be aware that you need also to clear arp cache on all neighbor devices on backbone links to make them aware of MAC address change or they will try to forward frames to old core nodes' SVI MAC address.

So after having made the VSS root bridge should be the right moment to do that and if possible I would use different ip addresses if not a clear ARP on neighboring devices is needed.

Hope to help

Giuseppe