Google DNS --- Figuring out which DNS Cluster you are using
ESundberg at nitelusa.com
Thu Aug 24 04:41:21 UTC 2017
Shaun, Good catch!!!
I would be nice if this was lowered to 1 second.
#dig o-o.myaddr.l.google.com -t txt @184.108.40.206
;; ANSWER SECTION:
o-o.myaddr.l.google.com. 51 IN TXT "220.127.116.11"
o-o.myaddr.l.google.com. 51 IN TXT "edns0-client-subnet 18.104.22.168/24" <<< Not my ip but someone from this IP did query this 9 seconds ago.
From: Shaun [mailto:nanog at shat.net]
Sent: Wednesday, August 23, 2017 11:21 PM
To: Erik Sundberg
Cc: nanog at nanog.org
Subject: Re: Google DNS --- Figuring out which DNS Cluster you are using
On Wed, 23 Aug 2017 20:09:49 +0000
Erik Sundberg <ESundberg at nitelusa.com> wrote:
> Which Google DNS Server Cluster am I using. I am testing this from
> Chicago, IL
> # dig o-o.myaddr.l.google.com -t txt +short @22.214.171.124
> "126.96.36.199" <<<<<<DNS Server IP, reference the list above to get the cluster, Council Bluffs, IA
> "edns0-client-subnet 207.xxx.xxx.0/24" <<<< Your Source IP Block
Worth noting, this record has TTL 60 and caching can cause unexpected responses; you may have to try a few times to get the correct data. My first attempt gave me an unrecognized "edns0-client-subnet" and a Google IP from Finland when I was querying from Atlanta.
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