topic Re: Wireless Controller Design in Wireless

Wireless Controller Design

fatalXerror — Wed, 26 Jul 2023 09:13:58 GMT

Hi,

I would like to check if the following are feasible,

1. 4x WLC with foreign-anchor design (2x for internal with SSO HA and 2x for guest SSO HA) in primary DC and 2x WLC (1x for internal and 1x for guest) as N+1 HA in my DR?

2. In the event that all of my internal (not the guest) WLC in PDC goes down, the internal WLC located in DR will kicks-in automatically associating all access points, can I force my guest to use the guest controller in DR instead of the one in PDC?

Thank you

Re: Wireless Controller Design

Flavio Miranda — Wed, 26 Jul 2023 10:14:58 GMT

Hi @fatalXerror

This scenario seems to be possible but you need to ajust your expectation with this part "In the event that all of my internal (not the guest) WLC in PDC goes down, the internal WLC located in DR will kicks-in automatically associating all access points"

Only HA SSO provide you this level of redundancy. If the pair of wlc goes down in PDC, the AP will disconnect, will reload and will stablish a new capwap tunnel with DR. This process will take a few minutes depeding on the AP model and link speed.

Re: Wireless Controller Design

fatalXerror — Wed, 26 Jul 2023 10:36:14 GMT

Hi @Flavio Miranda , thanks for the help.

I think that's okay. May I ask, the SSO HA requirement needs to be in the same subnet or I can do SSO HA via L3 meaning different subnet? Thanks

Re: Wireless Controller Design

Flavio Miranda — Wed, 26 Jul 2023 10:58:06 GMT

Same subnet

Both devices must have redundant IPs in the same subnet. IP addresses used for redundancy must be unroutable without a gateway present in the subnet.

This is how the topology looks like.

Re: Wireless Controller Design

fatalXerror — Wed, 26 Jul 2023 11:08:01 GMT

Hi @Flavio Miranda , I see meaning I need to stretch my VLAN across two or multiple sites. In the SDA or ACI design, possible 1x WLC in each DCs then using SSO HA?

Re: Wireless Controller Design

Flavio Miranda — Wed, 26 Jul 2023 11:14:48 GMT

That would be recommended if you are able to extend the vlan between DCs. As long as you keep the traffic in Layer2, you can use separated geography.

Re: Wireless Controller Design

fatalXerror — Thu, 27 Jul 2023 02:04:27 GMT

Hi @Flavio Miranda , for the SSO HA of controller, the communication of my AP should be also be the same subnet as the controller or it is not necessary to be in same subnet? Thanks

Re: Wireless Controller Design

Flavio Miranda — Thu, 27 Jul 2023 08:22:23 GMT

Not necessary. As long as the AP can communicate with WLC, they will join.

Re: Wireless Controller Design

Rich R — Thu, 27 Jul 2023 10:45:00 GMT

Note the APs do not need to reload to switch to the backup (N+1) WLC - it's simply a CAPWAP restart.
The primary and secondary WLC should be configured in the AP HA settings and you should have mobility configured between primary and backup WLC.

Re: Wireless Controller Design

Rich R — Thu, 27 Jul 2023 10:46:52 GMT

As Flavio says no need for APs to be in the same subnet - in fact I'd say they should not be - but you do need to think about the discovery mechanism they'll use to find the WLC - I'd recommend DHCP with option 43 configured with primary and secondary WLC IPs.

Re: Wireless Controller Design

fatalXerror — Mon, 31 Jul 2023 10:54:26 GMT

Hi @Flavio Miranda / @Rich R , can I use different WLC model for the anchor?

Re: Wireless Controller Design

Flavio Miranda — Mon, 31 Jul 2023 11:18:36 GMT

Yes, you can. You can check on this guide they doing it with AirOS and IOS-XE

https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/213912-configure-mobility-anchor-on-catalyst-98.html

Re: Wireless Controller Design

Rich R — Mon, 31 Jul 2023 13:53:05 GMT

Yes as long as the mobility tunnel is compatible (new/old).

Re: Wireless Controller Design

fatalXerror — Tue, 08 Aug 2023 02:40:29 GMT

Hi, going back to Foreign-Anchor design, would it be possible that my corporate SSID is in local switching and my guest will be central switching making the guest gateway to be at the anchor WLC? Thank you

Re: Wireless Controller Design

Rich R — Tue, 08 Aug 2023 04:57:08 GMT

Yes. The APs should be in Flexconnect mode to support local switching on the corporate SSID and you can still have centrally switched WLAN(s).