I'm working on a project to merge an existing set of fabrics with a pair of brand new 6520 switches. Eventually all connections on the existing switches will be migrated to the new 6520's. Th existing fabric consists of 2x 48000's (6.1.1a), 4x 200E's (5.3.2a), 2x 3850's(5.3.2a). There is also another pair of 300's that are in their own fabric & I'm not certain what OS they're running.
I realize that ideally all switches should be running the same or close to the same version of OS prior to merging fabrics, however in this case, its obvious that the existing environment is already fragmented and seems to be working fine. Should I anticipate any significant problems merging the new 6520's, which will probably be running 7.X code? I would appreciate any suggestions or recommendations. Thanks!
Yes, I would anticipate problems. Even if it does finish the join, it might have some weird problems you wouldn't expect. You have many different ASICs running different FOS versions, and I doubt there's been a test of something like this.
I'd recommend starting by installing the lowest firmware those 6520s will support. Definitely 6x instead of 7x. That'll increase your chances of having this work... once you clean up and remove the old switches from the fabric, you can do an upgrade to 7.
I'd also recommend that you avoid running more cables between switches than necessary. When condor2 has to communicate with condor 1 ASICs about routing, there are some incompatabilities that become apparent when you go above 8 items in the routing database.
Thanks! That makes perfect sense. I'm interested to hear if anyone else has dealt with a similiar situation.
Bump. Any other thoughts or recommendations?