Move ISC from 10GB LACP ports to 40GB LACP ports

[Chris1]

I have a small issue that i'm sure im just missing the recommended way to fix this. We have a MLAG group the ISC is a LACP Lag Group, but is currently 2x10gb, i want to move this to 2 of the 40gb on my x670.

I'm not sure the recommended way to do this without downtime of the cluster. Normally i could add the ports to the lacp cluster and remove the old ones, but can't do that as A. one of the ports is the master and i don't think you can change the LACP master port... and B. can't have 10GB and 40GB ports in the same LACP group even temporarily...

So how do you guys recommend to handle this?

[Chris1]

... so basically just swap it lol I'll just turn up a new 40gb lacp group connect the cables disable the port on 1 side, and then run the command to disable the old 2 ports and enable the 2 new ports forcing it to jump from 10 to 40, maybe run a clear FDB just to force a refresh?

[Drew_C]

You shouldn't need to clear the FDB. When the 10G ports are disabled, the ARP and FDB entries for those ports will be removed. The switch will relearn on your 40G ports.
Also, make sure those 10G ports aren't part of your connection to the switch... you don't want to be dropped as soon as you disable them 

[Henrique]

Hi Chris, I believe you can keep those 2 40G ports disabled and cables connected, enable sharing and perform all MLAG/Vlan configuration on those new ports (LAG).

Then, just disable the 2 10G ports and quickly enable the 2 40G ports. MLAG peer will be reestablished with the new sharing (40G) and MLAG/FDB will be synchronized through that port.

I would recommend to perform this action in a MW or less critical time.