EWC 9120AX and layer 3 interfaces.

[rfalvarado]

Hello team.

We are doing a migration project from an old WLC5520 controller to a EWC9200.

In the old WLC it was possible to create a level3 interface for each interface, and then have a DHCP relay.

In this new controller I don't see this option possible, because although I can create interfaces with IP they don't respond to ping even from the same vlan.

Is this type of deployment possible with the EWC9200?

Thanks for your help.

[marce1000]

 - FYI :  https://www.cisco.com/c/en/us/products/collateral/wireless/catalyst-9800-series-wireless-controllers/guide-c07-743627.html#Wirelessclientinterfaces

 M.

[rfalvarado]

Hi Marce, thanks for your response.

Yes, I read:

Wireless client interfaces

For centrally switched traffic, it is mandatory to configure a Layer 2 VLAN mapped to the SSID, but the corresponding Layer 3 interface (SVI) is optional, unless you need the multicast DNS (mDNS) feature or DHCP relay functionality. This is different from AireOS, in which a dynamic interface (Layer 3 interface and related IP address) is required.

In my deployment I need level3 interfaces as I need to relay DHCP.

But in the EWC I don't see an option to configure the level 3 interface and associate it to the physical interfaces of the AP.

In deployments with WLC9800 I have found that option, but not in the EWC.

Regards.

[marce1000]

 - Why don't you define the dhcp-relay for the particular vlan on the core ?

 M.

[rfalvarado]

Yes, that's what we will do.
Thank you very much.

Roberto F.

[Rich R · Accepted solution]

You said EWC9200 but the subject line is 9120AX so I assume you're running EWC on the 9120 AP?

EWC on AP only supports flexconnect local switching so there is no reason to ever configure the layer 3 interface on the WLC - it must be done on the local LAN where the traffic breaks out - standard flex local switching.

https://www.cisco.com/c/en/us/products/collateral/wireless/embedded-wireless-controller-catalyst-access-points/white-paper-c11-743398.html

https://www.cisco.com/c/en/us/support/docs/wireless/embedded-wireless-controller-on-catalyst-access-points/215303-embedded-wireless-controller-conversion.html#anc2

EWC on Catalyst AP Limitations

• EWC is not capable of having its Gig 0 interface configured as trunk  <<<<<<<
• EWC does not support SVIs <<<<<<<
• EWC is not capable of performing central switching   <<<<<<<
• Gig 0 is the only interface that can be used as a Wireless Management
• All of the EWC traffic has to be sourced from Gig 0 interface (including radius, capwap control, licensing traffic, and so on..)
• EWC is not capable of performing embedded packet captures
• EWC does not support APs in sniffer mode
• EWC image does not boot up if there is another EWC, AireOS or 9800 WLC in the same broadcast domain. The AP will continue to function as a normal lightweight capwap AP until the other WLCs are removed from the network.
• When converting or upgrading EWC in a deployment with mixed AP models, it is required to have a functioning TFTP server

[rfalvarado]

Thank you very much for the clarification.

With the document you have attached everything is much clearer.

Regards.

Roberto Fernández.