DNS resolver broken again

billmcg · Jan 8, 2019, 1:58 AM

I routinely have this problem and its driving me crazy.

I can resolve a particular name from the diagnostics on my pfense box, but from internal machines it doesn't resolve.

I'm running DNS resolver with DNS Query forwarding. It seems to be intermittent too. Last time I posted about this the problem resolved itself a half an hour later. I'm getting so that I don't trust the dns resolver.

Is there some issue where it won't return addresses in private IP ranges?

billm@spy:~>dig rancher.***.com

; <<>> DiG 9.10.6 <<>> rancher.***.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 8480
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;rancher.***.com.		IN	A

;; Query time: 7 msec
;; SERVER: 192.168.223.254#53(192.168.223.254)
;; WHEN: Mon Jan 07 17:48:41 PST 2019
;; MSG SIZE  rcvd: 50

This is obsured but it totally resolves correctly from the pfsense box itself. WTF?

Oh...
https://www.netgate.com/docs/pfsense/dns/dns-rebinding-protections.html

Derelict · Jan 8, 2019, 3:37 AM

Sounds like you might have forwarding on and DNSSEC enabled and are forwarding to forwarders that don't properly forward the DNSSEC forwarding.

This is obsured but it totally resolves correctly from the pfsense box itself. WTF?

Yes. Unless you set the domain as a private domain in unbound it will not return RFC1918 answers to queries.