OPNsense Forum

English Forums => 25.7, 25.10 Series => Topic started by: Lu on January 14, 2026, 04:40:38 AM

Title: Dnsmasq not responding to some some DNS queries
Post by: Lu on January 14, 2026, 04:40:38 AM
I have a printer that makes DNS queries like any other device, mainly to reach machines on the LAN, but also to 3rd party services on the Internet. From what I can tell, Dnsmasq on OPNsense flat-out refuses to answer its DNS queries. I've done packet captures on the OPNsense device, to compare requests from my own machine (https://paste.c-net.org/GeniusesBucking) with those of the printer's (https://paste.c-net.org/CabbieTravis), and I don't know why they go unanswered. It waits and asks again with the search domain appended again, defensive-programming-style. I don't see anything blocking them when I watch the live view of the firewall when triggering queries from the printer.

Does anyone have any ideas about the cause, or what else I can do to diagnose it?

As a band-aid solution, I've had to configure it to use static IP addresses instead of names to get basic functionality, but that isn't sustainable.