DHCPDECLINEs

I’m losing my mind on this one, and so far I haven’t found an answer anywhere.

I’m running ISC DHCP server on an Ubuntu 20.04 box. It’s set up with four VLAN interfaces, each of which is tied to a bridge, and it’s been serving up DHCP fine.

Suddenly, I’m getting devices that are giving me DHCPDECLINE messages. Some times with an abandon - sometimes not.

When I get on my laptop (a MacBook Air), it falsely tells me that there is an ip conflict and it can’t get an IP address. I do static DHCP leases for known devices, so I know that’s not it. Even when I nuke the static DHCP lease and restart the server, I get the same issues. I just get them on a different IP address.

I’ve seen this across multiple device types, so it’s not like it’s just Apple devices or whatever.

It’s also across multiple VLANs, so I can’t isolate it that way.

Has anyone run into this? If so, what’d you do? This is honestly driving me crazy!!