Dnsmasq - doesn't work for ip4

Started by GreenMatter, March 03, 2026, 05:38:50 PM

Previous topic - Next topic
March 03, 2026, 05:38:50 PM Last Edit: March 03, 2026, 06:17:57 PM by GreenMatter
I've just configured (in 26.1.2_5) HA - CARP VIPs for WAN and all my vlans. I made sure that VIPs have correct netmask (same as respective vlan).
I use Dnsmasq DNS & DHCP as DHCP server (ip4, ip6 in RA mode: slaac and ra-names).
And once I switched over to VIPs I had lost ip4 DHCP connectivity. I verified VIPs netmasks, in dnsmasq there's no any relevant option except selecting interfaces and strict binding - which doesn't help.
When I manually assign in client ip4 address - all works fine, connectivity is flawless even with switching over between master and backup...

Have I missed something, how to fix it??

EDIT:
Both opnsense instances are virtualised - Proxmox VM
OPNsense on:
Intel(R) Xeon(R) E-2278G CPU @ 3.40GHz (4 cores)
8 GB RAM
50 GB HDD
and plenty of vlans ;-)

If you are running a HA setup then you need KEA DHCP Server : https://docs.opnsense.org/manual/dhcp.html ;)
Weird guy who likes everything Linux and *BSD on PC/Laptop/Tablet/Mobile and funny little ARM based boards :)

Quote from: nero355 on March 03, 2026, 06:27:31 PMyou need KEA DHCP Server
Thanks, just migrated to dnsmasq a few months ago... I also use wifi enterprise and freeradius.
For test purposes I configured KEA on one vlan (stopped dnsmasq), as per https://docs.opnsense.org/manual/kea.html, have added standby and primary HA peers (firewall rules as well) did synchronisation. KEA receives heartbeat but still nothing - I can't get assigned ip4 address in client.
OPNsense on:
Intel(R) Xeon(R) E-2278G CPU @ 3.40GHz (4 cores)
8 GB RAM
50 GB HDD
and plenty of vlans ;-)

As far as I can see, even KEA sends dhcp offers from interface address and not VIP. Is it correct?
OPNsense on:
Intel(R) Xeon(R) E-2278G CPU @ 3.40GHz (4 cores)
8 GB RAM
50 GB HDD
and plenty of vlans ;-)