Advice on Wireless Upgrade Path

[SchoolVolunteer]

I have been asked to recommend a plan to upgrade a local school's wireless network incrementally from a 2504 centrally controlled and switched system to WIFI6 over a period of a couple years. The motivation is to modernize the AP and WLC, and propose a refresh schedule going forward that keeps devices under support.

Current Environment is:

  WLC: 2504 with 27 of 30 licenses used

  APs: 2602*14 +3502*10 + 3602*1 + 2802*2

  Phy: 3 buildings next to each other w/ fiber between them, all on the same set of VLANs (no per building segmentation)

There is no reason to believe there will be growth in the number of Aps needed, so I am thinking of using an embedded wireless controller on 91xx devices w/ local switching. But, I am not sure how to get there.

Where I am stuck is:

It appears the 9100 EWC cannot manage the older Access Points.

Documentation says the EWC (or Mobility Express) cannot coexist on the same network with a WLC.

Q1: by coexist on the same 'network' does that mean same vlan? Could I run a WLC with CAPWAP traffic on  VLAN5 and EWC  on VLAN10 for example?

Q2: Does moving from 2504 to Mobility Express as an intermediate step help?

Q3: Any advice on how to do this?

[Leo Laohoo]

Q1:  Mobility Express can manage your 2800 -- And that's about it.  

[Ric Beeching · Accepted solution]

Q1: It means on the same VLAN because when APs did a L2 broadcast on boot they would get a response from both WLCs and would be confused as to which one to join. You can set the primary WLC to address this but you just run the risk of APs ping-ponging between the two. If your ME/EWLC exist on a diff subnet from a management perspective then you address this as you've outlined, but you're still running two separate RF networks.

Q2: Not really, the 2504 can do all the same things and more than a ME AP right now so no point using it. However, your main issue is most of your APs can't go past 8.5 software and you need 8.10 to run the 91xx series APs so that means you will be forced to run two separate deployments. Easiest thing to do right now therefore would be to keep your 2504 with all the older APs running off it and deploy any new APs on a separate network/WLC.

Q3: As above, just have another separate management subnet for your newer APs but you can still put clients on the same access VLANs provided DHCP is hosted centrally. The risk is you may have some conflicts in RF (unless you can have an RF leader between the two WLCs and I don't think this is possible with ME/EWLC) and clients will obviously experience different performance with the newer APs. That said, it allows you to gradually replace old with new over time if you can't just do a full refresh.

If you have virtual resources available I would consider deploying a 9800-CL controller at least to do your new APs over the embedded one or spring for a 9800-L which is the 2504 successor for IOS-XE.