How to remove stuck DHCP lease

[Lecso11]

I have defined a few static leases for devices I always want on the same address. However after upgrading these devices I cannot release the old lease reserved for the old MAC address. These leases have the epxiration date of 1970-01-01 01:00:00.
How can I delete these entries?

[Nullman]

Remove static entry, restard DHCP service, restart the client and see if it receives IP address other than static entry. If it does, re-create the static entry, and you should be good.

[DROOG]

I'm experiencing the same issue with a device I no longer have connected. I removed the static lease but appears as a dynamic lease with that same expiration date of 1970-01-01 01:00:00. I don't know how to get rid of that lease.

[Patrick M. Hausen]

Which DHCP server? There should be a button to delete a lease at the right. Do you use a UI theme?

[nero355]

There should be a button to delete a lease at the right.

KEA does indeed, but IIRC from some topics DNSmasq does not ?

[Patrick M. Hausen]

ISC did, Kea does. Sorry, I expected DNSmasq to have the same feature. Especially because DNSmasq was pushed as *the* ISC replacement first.

I am very satisfied with Kea at its current state. Thanks for all the work that went into this!

[julsssark]

I ran into this last week when I rebuilt some VMs. I use DNSmasq and my understanding is that there is no clean way to remove a lease. My leases did not have dates in the past and all I needed to do was wait a day.

See here for a recent thread on this topic and why it requires an upstream solution: https://github.com/opnsense/core/issues/9747