Can ISC and KEA DHCP coexist?

[c-mu]

I have many VLANs where the classic ISC DHCP SErver does its job. Now I wanted to deactivate ISC and activate KEA in one VLAN as a test, but I can't get a DHCP lease. I don't see any errors in the log file and the KEA service starts. Do I have to disable ISC on all interfaces for it to work?

I have already configured the corresponding subnet in KEA and checked it three times. But after deactivating ISC and activating KEA on that specific VLAN, my client does not get a DHCP lease on the VLAN.

Thank you!

[franco]

No, as long as ISC DHCP is running you cannot run Kea. This is by ISC DHCP design claiming the DHCP server port for itself exclusively. Kea doesn't do that, but also can't do anything about it.


Cheers,
Franco

[c-mu]

Hi Franco,
even if ISC is deactivated on the interface and only KEA is listening?
Well, then I have to change all interfaces at once.

Many thanks for the quick answer!

[franco]

Kea will bind to a specific interface per instance. ISC DHCP will bind to all even if just enabled for one.


Cheers,
Franco

[c-mu]

I am a bit confused. is there a general “Disable ISC” option? I have now disabled the server for all interfaces below ISC and enabled kea. I also get an IP address, but apparently not from KEA, the log file + the lease overview remains empty.

[franco]

> is there a general “Disable ISC” option

No. Disable all DHCPv4 servers and best to reboot as well.


Cheers,
Franco