Yesterday, the DHCP service on my Omada network stopped working.

I have since read this forum thread, which explains that this is caused by a firmware bug.

The problem is:  I can't connect to the router since all my DHCP leases went up.  I tried using Ethernet and setting a fixed IP to my computer and couldn't get to my Omada controller.  Of course, I could also not connect directly to the router interface, since the password has been randomly set by the controller.

Now here is where I am stuck:  I disconnected all network interfaces except my computer (in the LAN port), then held the reset button until it fast-blinked.  After restarting, the router is stuck with the System light slow-blinking, there is still no DHCP.  When I set my computer's IP as 192.168.1.100 and the gateway to 192.168.1.1, I can access the login page at 192.168.1.1, which means the factory reset has failed - these are the setting for my local network and not the defaults.

So, how do I force a complete reset of the router and/or reflash it?  I have used the reset procedure here.

After resetting the router, it still did not respond to DHCP requests:  I used the Windows command line to execute ipconfig /renew and nothing came back.

When I set my computer's IP as 192.168.0.20, I could route through the gateway to my Linux Omada Controller.  I logged in it then instructed it to adopt the router.  It went through the different normal adoption states (configuring, provisioning, etc.) but the gateway's state never became functional.  I disconnected my computer from the router, then reconnected with IP settings back to automatic.   No address gets assigned to the computer, and the router now responds to 192.168.1.1 (as configured by the controller, I presume).

So, how do I restart the DHCP service?