System Administration & Network Administration
bind internal-dns dhcp-server isc-dhcp ddns
Updated Sat, 24 Sep 2022 10:45:48 GMT

ISC DHCP/DDNS setup: Static entries for non-dhcp clients

I have set up a local network with ISC BIND9 and DHCP service. New leases trigger the DHCP to add an A and PTR record which works perfectly.

I also added lots of static host entries in the dhcpd.conf. Now I noticed that the DDNS update only works for clients that actually request a lease from the DHCP server. I have a few devices in the network that do not support DHCP. I still added static entries in the dhcp.conf. For those, no lease is requested and now no DNS-records are created. What options do I have to add those static entries in a way that DNS-records get created?

I would prefer to only use the dhcpd.conf if possible. Greatly appreciate any suggestions!


I stumbled across this post when looking for info on another issue I have with ISC-DHCP and BIND9.

If your devices aren't requesting DHCP leases then adding static entries to dhcpd.conf won't matter. If you've set a static IP on the devices itself, you'll need to add a DNS A record for those devices.

You'd do it like this:

sudo rndc freeze yourzone
sudo nano /etc/bind/db.yourzone

add your entry at the bottom like so

hostname         A          192.168.X.X

save and exit (but don't forget to increment the serial number at the top by one)

sudo rndc thaw yourzone

Maybe you've already fixed this yourself, but it might be helpful to someone else!

Do the same to the reverse lookup zone if you have one configured.

EDIT: Also make sure the static IP you set is not in the DHCP range, to avoid IP conflicts.