Connecting 5508 WLC to Meraki MS

[Ira]

We've switched from Catalyst to MS but, for budget reasons, haven't retired two 5508 WLC and Aironet APs.  Does it make sense to put a Catalyst between the WLC and MS with a LAG channel connecting the WLC and an LACP channel for MS?  Or is this something that looks good on paper but doesn't have real world benefit?  

[KarstenI]

No, the Meraki MS needs LACP for Etherchannels, but the 5508 doesn't support that and doesn't allow LACP to be configured on the neighbouring switch:

https://www.cisco.com/c/en/us/td/docs/wireless/controller/8-5/config-guide/b_cg85/ports_and_interfac...

[PhilipDAth]

I never bothered with channel aggregation for any WLC I deployed.  You can configure a backup and primary port on the WLC for redundancy.

[GIdenJoe]

That was the old way of doing things 😉
Usually from the 2504 forward they always used LAG mode since you didn't have to bother with load balancing your interfaces manually.
More recent Catalyst controllers usually come with the option to do port-channels on regular ports or smaller port-channel on the high speed interfaces but they do support lacp.