Lots of unsuccessful DHCP offers and probably loop warnings

RouterOS General
1

Hey guys!

I have an irritating problem in our LAN network. The sympoms are that we have 19 switches and around 25 access points in our network, and in 10-15 min periods the part of the network loses the connectivty and I can see tons of “DHCP offer without success” and “received with own MAC address… probably loop” warning messages in the logs.
On the wireless side we use Unifi Access Points. I have checked and for ensurance set all of the ports to trunk, and activated RSTP on every device on the related ports. The problem still exists. There are two vlans in the network. Can anyone know what can cause this, or how do you troubleshoot a possible loop in such a LAN?
Is it possible that the AP’s losing wired uplink connectivity, switch for a wireless uplink, and therefore creating a broadcast loop if two AP’s connected to each other, plugged on different switches?
Thank you for your help beforehand.

Cheers, G.

2

Did you look at lease times as well. I know right an annoying thing with APs and attached devices.

3

Yes, the lease times are 10mins, but the issue occurs more frequently than that.

4

When using Unifi, make sure you have the management network (untagged on the APs) separate from your user networks (VLAN tagged).
Don’t allow users on the management network. I know it is the default to have that.