Charter DNS servers returning invalid IP addresses

[Sylvain BAYA]

Dear NANOG-er,

Hope this email finds you in good health!

Please see my comments below, inline...

Thanks,


Le 25/10/2023 à 18:50, Jason J. Gullickson via NANOG a écrit :

A dig against Google's DNS servers correctly returns 4 A records:


dig bonesinjars.com 8.8.8.8

I've been working for a week or so to solve a problem with DNS resolution for Charter customers for our domain bonesinjars.com.  I've reached-out to Charter directly but since I'm not a customer I couldn't get any help from them.  I was directed by a friend to this list in hopes that there may be able to reach a Charter/Spectrum engineer who might be able to explain and/or resolve this one.

...instead of the above, you could try the following command:

`dig bonesinjars.com. @9.9.9.9 +nsid +edns=0 +all +short`

Please, do note the sign `@` and the trailing dot `.`

[...]
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 26879
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;8.8.8.8.                       IN      A

...this is unexpected! given what you said.

;; Query time: 35 msec
;; SERVER: 127.0.0.53#53(127.0.0.53) (UDP)
;; WHEN: Mon Oct 23 10:26:32 CDT 2023
;; MSG SIZE  rcvd: 36





dig bonesinjars.com 24.196.64.53

Verizon, AT&T, Comcast and all other DNS servers we tested return the same 4 A records.  However the same dig against a Charter DNS (24.196.64.53) returns only 127.0.0.54:

`dig cmnog.cm. @24.196.64.53 +nsid +edns=0 +all`

or

dig cmnog.cm. @`dig -x 24.196.64.53 +short` +nsid +edns=0 +all

; <<>> DiG 9.16.1-Ubuntu <<>> bonesinjars.com 24.196.64.53
[...]
;; QUESTION SECTION:
;bonesinjars.com.        IN    A

;; ANSWER SECTION:
bonesinjars.com.    60    IN    A    127.0.0.54

[...]

;; QUESTION SECTION:
;24.196.64.53.            IN    A

...it's not what you wanted to test!
`dig` understood it otherwise.

...associating the @ sign with the above IPv4 address
would have corrected the behavior of `dig`:
*@24.196.64.53*

;; ANSWER SECTION:
24.196.64.53.        86400    IN    A    24.196.64.53

;; Query time: 27 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
[...]


Any help understanding and addressing this is greatly appreciated!

Hi Jason,

Thanks for your email, brother.

...you should note that:

n#1. each of the command you shared above is not
producing the expected behavior. Please replace
it by the one i suggested, and observe the diff.

n#2. the DNS resolver you try to use appears to not
being, actually, available for any request.
Just try: `dig @24.196.64.53 cm.` or even:
`dig @24.196.64.53 ns1.charter.com.`

Maybe you should, first clarify what you needed to
achieve.

That said! maybe it's a simple matter of changing
a DNS resolver? have you ask to someone within
Charter's network to try with quad9, for example?
...or any other public DNS resolver, to be fair.

Hope this helps!

Shalom,
--sb.

Jason

--
Best Regards !

baya.sylvain [AT cmNOG DOT cm]

|cmNOG's Structure <https://www.cmnog.cm/dokuwiki/Structure>|cmNOG's Surveys <https://survey2.cmnog.cm/>|Subscribe to cmNOG's Mailing List <https://lists.cmnog.cm/mailman/listinfo/cmnog>|

__

#‎LASAINTEBIBLE‬|‪#‎Romains15‬:33«*Que LE ‪#‎DIEU‬ de ‪#‎Paix‬ soit avec vous tous! ‪#‎Amen‬!*» #‎MaPrière‬ est que tu naisses de nouveau.#Chrétiennement‬ «*Comme une biche soupire après des courants d’eau, ainsi mon âme soupire après TOI, ô DIEU!*» (#Psaumes42:2)

OpenPGP_0x0387408365AC8594.asc
Description: OpenPGP public key

OpenPGP_signature.asc
Description: OpenPGP digital signature