cancel
Showing results for 
Search instead for 
Did you mean: 

Migrate from 1GB to 10GB uplinks - help?

Migrate from 1GB to 10GB uplinks - help?

Frank
Contributor
I have a simple setup - two core switches (8800s), several edge switches (460s) connected like this: 8800s are running 16.1.3.6-patch1-9, 460-1 is on 15.4.1.3, 460-2 is on 15.6.1.4.

50e1f0c24ad444b68639a7f4721868da_RackMultipart20170308-76557-z2351h-LACP2_inline.png


My problem is that the 460s are on 1GB fiber (ports 55,57) and I need to upgrade them to 10GB while everything stays up and running, i.e. the devices connected to the 460s don't lose access to the network.
The end goal is that the 10GB uplinks also need to be in ports 55,57 (for sanity's sake) Ideally, the corresponding ports in the 8800 should also stay the same (sanity!), but I could be persuaded to use different ports.

If I understand correctly, I can't just replace the SFPs one by one because of port speeds and sharing configs/mismatches.
Physically, the two 460s are right on top of each other, so I could run something between them and use that as an alternate path, but I also hear that loops are deadly. I don't think I can easily define that as a 460-ISC MLAG, as I'd have to put the ports on the 8800 side into sharing mode, affecting vlan-port associations to the 460. (Let's say vlan 1 goes to 460-1 vlan 2 goes to 460-2, let's say on the 8800s port 1:11 goes to 460-1, port 1:12 goes to 460-2. What all would die if I group 1:11 and 1:12? At least all vlans pointing to 1:12 would have an issue, right?)

On the other hand, I'm not currently running spanning-tree. If I connect the 460-1/2 with a gig-ether (or two , shared) in a non-MLAG setup, make sure all vlans that exist on both switches are defined to go to to both switches (and the connection between the 460s) and define spanning-tree on all the vlans, would that get me to a point where I can just rip out one 460's fiber uplink, replace it with 10G, then do the other 460, then disconnect the link between the 460s and kill off STP?

I've never configured STP on Extreme switches, btw. Especially not with share groups and an MLAG.

So, how can I pull this off without downtime (or downtime in the "few seconds" range)? Would STP be viable? Is there something better I can do during the fiber/SFP replacements?

Thanks for your help!
Frank
19 REPLIES 19

Frank
Contributor
Quick update:

I reconfigured the redundancy mode to use "link on", and it did indeed work as advertised! Whatever happened to me yesterday with the traffic/spikes must have been something completely different. Who knows what I did...

During failover from my fiber group to the redundant link group, I may have lost one ping packet, so I'd say 1 second or less to fail is about right.

Re-establishing the link (10G, 2-port share to the MLAG on the 8800s) took about 3-5 seconds.

Thank you very much for all your help, especially Michal for being "first" with the much easier approach for a backup link, and Eric for probably having the entire Q&A section memorized so he could link to all kinds of useful articles!

Have a great weekend!

Frank

Erik_Auerswald
Contributor II
Hi Frank,

according to How to validate if a software controlled redundant port is set up to block traffic?, TX and RX should be blocked.

Did you verify if the received traffic is actually forwarded to any port or local interface? I'd do that in a lab setting or very carefully...

If you configure redundant ports on both switch-1 and switch-2 before enabling the physical ports, you should see no traffic even with "link on."

Erik

Eric, check my response above

You are correct, you can use the redundant port on one switch only, as the other does not know about it.
GTM-P2G8KFN