Cisco 9120 AXI - Downgrade from EWC to Lightweight

[PHaug]

Hi, 
One of my customers has 67 Cisco 9120AXI access points at one of their locations, and 32 of them are running running EWC image. 

There is also 19 Cisco 2700I access points on the location, but they are outside the scope of my question. 

All of theese access points are Connected to a central WLC (Cisco 9800 Cloud), serving multiple locations.

Whenever connectivity to the Central WLC is lost we have experienced that one or multiple 9120 access points have started operating as a EWC, and multiple of the other access points have joined this EWC. 

When the Central WLC is brought back up again, many of the access points are still connected to the EWC. We can perform a shutdown / no shutdown on the access point's switch port, but due to administrative distance one of the other 9120 access points will resume the role as EWC, prioritized over the 9800. 

Normally one can convert the EWC to Lightweight CAPWAP mode with the "ap-type capwap" command. 
The access points will still start operating in EWC mode whenever connection to Central WLC is lost, or upon a reboot. 

From what I have seen, one can install software for the 9120 AXI to operate as lightweight access point. 
https://www.cisco.com/c/en/us/support/wireless/catalyst-9120ax-series-access-points/series.html#~tab-downloads

I have seen a lot of guidelines for migrating from CAPWAP to EWC, but none the other way. 
How does one install this software from console access?

Will the Lightweight AP 15.3.3.-JPN1 software remove all of the 9120's EWC functionality, or is there some additional ROM-software which makes the 9120 capable operating as EWC?

[JPavonM]

This command on the AP running as EWC "ap-type capwap" should do the trick.

If it's not, the recovery method would do the trick.

[jagan.chowdam]

Converting EWC Back To Lightweight CAPWAP Mode

Login to the ap shell from the EWC. You should see an ap prompt which is the ap name not the EWC name.

If AP running in EWC mode needs to be converted back to lightweight capwap mode, it can be done via:

AP1#ap-type capwap
AP is the Master AP, system will need a reboot when ap type is changed to CAPWAP
. Do you want to proceed? (y/N) y

Important: This command will perform a complete factory reset of both AP and EWC partition. Make sure to backup existing EWC configuration before conversion.

CJ

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[Rich R]

I wrote about observing the same behaviour on another thread recently.  As @JPavonM said the AP recovery re-flash method guarantees to remove the EWC capability from the AP completely.

Of course you can also issue the command to join the WLC to all the APs from the EWC AP.

You can also try the option 43 method.  I haven't tested this myself so not sure how effective it will be in the scenario you mention - you might still need to reboot the APs.

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

Converting EWCs to CAPWAP using option 43

DHCP option 43 is a vendor-specific option and is used for providing WLC IP addresses to the access point. Using option 43 with a specific subtype option, you can have the EWC convert to CAPWAP and join a WLC appliance or virtual controller. After the AP receives DHCP option 43 and subtype 0xF2 at bootup, the AP type will be converted to CAPWAP, and the AP will follow the regular joining process.

The DHCP configuration on the switch is shown below.

Switch(dhcp-config)#option 43 hex F2056464645801