Hi, I’m pretty new to VyOS. I like it a lot so far, but I’m having some trouble with DNS resolution an wonder if I did something wrong.
Brief overview of my setup:
I have two VyOS (nightly) routers with VRRP and two piholes in my LAN.
The routers have the piholes configured as their DNS-Servers and the DNS Forwarding Service is set to listen on the VIP-addresses and use the system-dns.
This works fine for a limited amount of time, after which the routers stop forwarding queries to the piholes and start answering requests with NXDomain.
In this tcpdump the router answers the query right away without sending one to pihole:
16:56:20.781138 eth1 In IP 192.168.1.183.57236 > fw.localdomain: 46956+ A? libreddit.localdomain. (33) 16:56:20.781138 eth1 In IP 192.168.1.183.57236 > fw.localdomain: 50016+ AAAA? libreddit.localdomain. (33) 16:56:20.781336 eth1 Out IP fw.localdomain > 192.168.1.183.57236: 46956 NXDomain 0/1/0 (108) 16:56:20.781363 eth1 Out IP fw.localdomain > 192.168.1.183.57236: 50016 NXDomain 0/1/0 (108)
The right behavior is in this examlple:
21:35:32.632867 eth1 In IP 192.168.1.183.47981 > fw.localdomain: 6424+ A? forum.vyos.io. (31) 21:35:32.632867 eth1 In IP 192.168.1.183.47981 > fw.localdomain: 11801+ AAAA? forum.vyos.io. (31) 21:35:32.633354 eth1 Out IP fw01.capra.65512 > pi.hole.domain: 40853+ [1au] A? forum.vyos.io. (42) 21:35:32.633550 eth1 Out IP fw01.capra.13504 > pi.hole.domain: 16171+ [1au] AAAA? forum.vyos.io. (42)
I can solve this issue by restarting the pdns-recursor service, but that’s only a temporary fix.
Any ideas on how to fix this permanently? I tried larger, smaller and no DNS-cache but that seems to have no influence. Any help and questions welcome.
I’ve read Debugging — VyOS 1.4.x (sagitta) documentation but still haven’t been able to enable any sort of debug-logging for the forwarder. I tried
touch /tmp/vyos.dns.forwarding.debug touch /tmp/vyos.dns.debug
and a couple of other variants to no success