Portchannel fails on stacked 2960-s switch to UCS 200

[Preston Kilburn]

I converted a set of switches last night (3650-lan base 12.2) to a new stack of qty 2 - 2960s (IOS 15 latest) with flexstack on them.  They are connecting to a UCS 200 running CUCM and Unity, managed by VMWare w/o Virtualcenter.  For whatever reason I had issues when I had the ports on different switches that were connected with flexstack (meaning when I had one port on 1/0/30 and another on 2/0/30 it would fail).  When I put the ports onto one physical switch it worked fine.

Reading through the documentation I see that there are some issues with pagp and possibly lacp on multiple switches in a stack.

Can someone recommend a channel-mode for the port channels' configuration that will make it work across two physical switches?  Seems dumb to use a flexstack if I can't break the load between both switches in case something happens.

[acampbell · Accepted solution]

Hi,

You can only use LACP or MODE ON channelling if you need to use

ports from different switches,

PAGP will NOT operate through the stacking elements

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960/software/release/12-2_55_se/configuration/guide/scg_2960/swethchl.html#wp1275503

Regards

Alex