MR33s not releasing old static after factory reset

[MerakiMed]

We acquired some MR33s and moving them to our dashboard. I frequently have problems with registration even though I was able to add them to inventory and to a specific network. To troubleshoot I've run packet captures of the switch port of the MR33. What I am seeing *after the factory reset* are references to both the old IP address and gateway and the new IP DHCP assigned address. It doesn't make sense to me since it seems like factory reset should mean fresh as if out of the box - no? After several factory resets, adding IPv6 to the VLAN shaking the monitor the new address finally seems to take effect and the AP registers. I'd guess after an hour or so of fingernail biting. I've been telling the local techs to hold down the reset button 30 seconds since the 20 second is not effective but same result. 

One other thing I tried was creating a temporary vlan/subnet to get the MR33 to register with its old address thinking may then I could specify the DHCP there. That's next. But any thoughts on why I'm seeing the old addressing after factory reset?

[alemabrahao]

I suggest you to open a support case.

[Madhan_kumar_G · Accepted solution]

Hi,

If a device is still in a network after being factory reset, it will re-download its previous configuration when it comes back online. This includes any previously assigned static IP addresses. If the configuration needs to be completely reset, make sure to remove the device from its network before resetting to factory defaults. 

[test2]

I have some MX that I am trying to decommission and I have it disconnected from the WiFi and use the reset button and the static ip still populates. 

[test2]

So after testing this the factory reset is useless really because the old config downloads after you factory reset it and reconnected to a network. I had the device removed form my network and unclaimed and it still repopulated the old config after I factory and then reconnected to a network. The only way to remove the config is to create a dummy config and then removing it from the network. Using the reset button will is pointlet after that since it is going to reload the dummy config again.