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IPv6 reverse dns broken, still returns SERVFAIL

As discussed here numerous times (see [1]. [2]. [3] for examples), IPv6 reverse DNS is broken for Spectrum's prefix 2606:6000::/32.  Lookups are returning SERVFAIL instead of NXDOMAIN:

$ dig -t ns -x 2606:6000:760f:2f00::1

; <<>> DiG 9.10.3-P4-Debian <<>> -t ns -x 2606:6000:760f:2f00::1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 35619
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.f.2.f.0.6.7.0.0.0.6.6.0.6.2.ip6.arpa. IN NS

;; Query time: 2608 msec
;; SERVER: 10.23.5.1#53(10.23.5.1)
;; WHEN: Wed Jan 03 15:57:59 PST 2018
;; MSG SIZE  rcvd: 101

 

I believe this issue is causing Google to flag some of my actions as suspicious, and forcing me to authenticate many times.

 

 

[1] - http://forums.timewarnercable.com/t5/IPv6/IPv6-reverse-DNS-still-broken-after-nearly-two-years/td-p/...

[2] - http://forums.timewarnercable.com/t5/IPv6/Reverse-DNS-lookups-for-TWC-IPv6-addresses-return-SERVFAIL...

[3] - http://forums.timewarnercable.com/t5/IPv6/Reverse-DNS-not-working-for-my-IPv6-addresses-ZIP-78729/td...

1 REPLY
Expert

Re: IPv6 reverse dns broken, still returns SERVFAIL

What modem are you running?

what does an IPv4 vs IPv6 tracert to the dns look like?

IPv6 is notoriously slower and I believe it's timing out.