If an authoritative server returns invalid RRType in the answer, kresd goes along
GitBook CDN returns A record on any query (now at least limited to A and AAAA), and IPv4 is now fine:
ondrej@komorebi:~/Projects/knot-resolver (master)$ dig +dnssec +multi +time=60 +retry=1 -p 50168 @::1 cdn.gitbook.com.
; <<>> DiG 9.10.3-P4-Debian <<>> +dnssec +multi +time=60 +retry=1 -p 50168 @::1 cdn.gitbook.com.
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 33743
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags: do; udp: 4096
;; QUESTION SECTION:
;cdn.gitbook.com. IN A
;; ANSWER SECTION:
cdn.gitbook.com. 3600 IN A 95.85.1.232
;; Query time: 880 msec
;; SERVER: ::1#50168(::1)
;; WHEN: Mon Feb 20 11:09:56 CET 2017
;; MSG SIZE rcvd: 60
But AAAA query returns A
record which is invalid for this type of query.
ondrej@komorebi:~/Projects/knot-resolver (master)$ dig +dnssec +multi +time=60 +retry=1 -p 50168 @::1 IN AAAA cdn.gitbook.com.
; <<>> DiG 9.10.3-P4-Debian <<>> +dnssec +multi +time=60 +retry=1 -p 50168 @::1 IN AAAA cdn.gitbook.com.
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55917
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags: do; udp: 4096
;; QUESTION SECTION:
;cdn.gitbook.com. IN AAAA
;; ANSWER SECTION:
cdn.gitbook.com. 3600 IN A 95.85.1.232
;; Query time: 110 msec
;; SERVER: ::1#50168(::1)
;; WHEN: Mon Feb 20 11:11:22 CET 2017
;; MSG SIZE rcvd: 60
@pspacek Could you write tests with @sbalazik or @ikrumlova ?