I created a test environment with one DECO and a DHCP-range from 192.168.0.250 - 192.168.71.250.

The client device had a setup with randomized MAC-addresses. Addresses 192.168.0.250, 251, 253, 254 were given, and after that 192.168.1.1, 2, etc was given.

So DHCP-range looks fine. This test was without the switch and VLAN in between.

Does anyone know how to debug the DECO? Or get more information from it?

  @SVP I don't have an answer for you but I have had problems with DHCP server on Orbi systems stop issuing IP addresses.

But I was wondering why you need to use a 16 bit subnet mask?

The XE75 default 22 bit subnet mask already provides over 800 addresses and I assume that still gives plenty of room to avoid address reuse problems if there were going to be any (if that's your thinking there).

Why risk confusing support if tou ever need to log an actual support case, you'll probably end up with a "not supported" response even though it's not valid, 

raven-au wrote

  @SVP I don't have an answer for you but I have had problems with DHCP server on Orbi systems stop issuing IP addresses.

 

@SVP I believe this problem was due to the number of devices I had growing beyond around 60 -70 but I can't be sure.

 

My thought was there was a race updating the leases data file (assuming there is such a file) when there are many concurrent address requests such a when the system booted up.

In my case, once the system was up and running, I didn't see a problem but trying to re-boot could take a long time.

 

It's unlikely your seeing the same problem and the DHCP server on the Decos is probably different to the one on the Orbis but these are the sort of problems one can expect once usage starts to become demanding.

  @SVP and btw I have around 90-100 devices now and I didn't see DHCP address allocation problems with the XE75 for the couple of months I was using them.

Not sure why I didn't see a problem since you do seem to be seeing one ...