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24.7 Production Series / Issue with UnboundDNS not answering DNS requests for local hostnames

« on: November 04, 2024, 02:41:17 am »

Hi guys,

I've got a strange issue where DNS lookup requests to UnboundDNS/opnSense aren't being answered. The only way I can get it working again is to restart the UnboundDNS service. These are requests to hostnames which should have been registered in DNS by DHCP. There's nothing of interest in the unbound logs.

Any ideas on how I can troubleshoot this?

Original dig request before restarting unbound:

Code: [Select]

dig @10.11.12.1 buildserver.lan

; <<>> DiG 9.10.6 <<>> @10.11.12.1 buildserver.lan
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 40384
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;buildserver.lan. IN A

;; AUTHORITY SECTION:
. 2111 IN SOA a.root-servers.net. nstld.verisign-grs.com. 2024110301 1800 900 604800 86400

;; Query time: 3 msec
;; SERVER: 10.11.12.1#53(10.11.12.1)
;; WHEN: Mon Nov 04 11:31:42 AEST 2024
;; MSG SIZE  rcvd: 119

After restarting unbound service:

Code: [Select]

dig @10.11.12.1 buildserver.lan

; <<>> DiG 9.10.6 <<>> @10.11.12.1 buildserver.lan
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 56202
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;buildserver.lan. IN A

;; ANSWER SECTION:
buildserver.lan. 3600 IN A 10.11.12.225

;; Query time: 4 msec
;; SERVER: 10.11.12.1#53(10.11.12.1)
;; WHEN: Mon Nov 04 11:32:27 AEST 2024
;; MSG SIZE  rcvd: 60

Here are my unbound DNS settings: