Google Resolver 8.8.8.8 Selectively responding to RDNS requests
I have a /24 in an Internap colo and use Google Resolver 8.8.8.8 on all my machines. Google will not consistently respond to RDNS lookups from source IP X.X.X.1 but will respond consistently if I change the IP address of the machine to X.X.X.2. I have proven the DNS response is never returned using tcpdump. It's positively not a local networking issue as changing my resolver to 4.2.2.2 (Level 3) while the machine uses X.X.X.1, the RDNS responses arrive without fail. Has anyone else seen this sort of selective response by Google? Do they maintain some sort of black list?
On Fri, May 23, 2014 at 03:31:42AM -0400, Blake McKeeby <blake.mckeeby@gmail.com> wrote a message of 10 lines which said:
Has anyone else seen this sort of selective response by Google? Do they maintain some sort of black list?
I would suggest it is probably more load balancing by hashing the source IP address then a black hole.
Hmm interesting, good point, never thought of that. If that is the case, then the conclusion would be that this issue is affecting more than just my X.X.X.1 but rather all source IPs whose hashed value is the same as my X.X.X.1? On May 23, 2014, at 3:56 AM, Stephane Bortzmeyer <bortzmeyer@nic.fr> wrote:
On Fri, May 23, 2014 at 03:31:42AM -0400, Blake McKeeby <blake.mckeeby@gmail.com> wrote a message of 10 lines which said:
Has anyone else seen this sort of selective response by Google? Do they maintain some sort of black list?
I would suggest it is probably more load balancing by hashing the source IP address then a black hole.
On May 23, 2014, at 3:00 PM, Blake McKeeby <blake.mckeeby@gmail.com> wrote:
If that is the case, then the conclusion would be that this issue is affecting more than just my X.X.X.1 but rather all source IPs whose hashed value is the same as my X.X.X.1?
It's unlikely the hashing is that simple. Also, you should check to ensure your .1 isn't being abusive. ---------------------------------------------------------------------- Roland Dobbins <rdobbins@arbor.net> // <http://www.arbornetworks.com> Equo ne credite, Teucri. -- Laocoön
You should at least be using 8.8.4.4 for some of your queries, does it work? -- ERIC HENSON Solutions Architect for Systems Organization PFSweb | www.pfsweb.com p: 972.881.2900 x3104 m: 972.948.3424 -----Original Message----- From: Outages [mailto:outages-bounces@outages.org] On Behalf Of Roland Dobbins Sent: Friday, May 23, 2014 3:26 AM To: Outages@outages.org (outages@outages.org) Subject: Re: [outages] Google Resolver 8.8.8.8 Selectively responding to RDNS requests On May 23, 2014, at 3:00 PM, Blake McKeeby <blake.mckeeby@gmail.com> wrote:
If that is the case, then the conclusion would be that this issue is affecting more than just my X.X.X.1 but rather all source IPs whose hashed value is the same as my X.X.X.1?
It's unlikely the hashing is that simple. Also, you should check to ensure your .1 isn't being abusive. ---------------------------------------------------------------------- Roland Dobbins <rdobbins@arbor.net> // <http://www.arbornetworks.com> Equo ne credite, Teucri. -- Laocoön _______________________________________________ Outages mailing list Outages@outages.org https://puck.nether.net/mailman/listinfo/outages ------------------------ This email was scanned by BitDefender.
Check out this page and the link from there to the Google Public DNS User Group or the Issue Tracker for reporting issues: https://developers.google.com/speed/public-dns/docs/using?csw=1#troubleshoot... Hope that helps, -Scott On 05/23/2014 03:31 AM, Blake McKeeby wrote:
I have a /24 in an Internap colo and use Google Resolver 8.8.8.8 on all my machines. Google will not consistently respond to RDNS lookups from source IP X.X.X.1 but will respond consistently if I change the IP address of the machine to X.X.X.2. I have proven the DNS response is never returned using tcpdump. It's positively not a local networking issue as changing my resolver to 4.2.2.2 (Level 3) while the machine uses X.X.X.1, the RDNS responses arrive without fail.
Has anyone else seen this sort of selective response by Google? Do they maintain some sort of black list?
_______________________________________________ Outages mailing list Outages@outages.org https://puck.nether.net/mailman/listinfo/outages
Great, I agree that it is because traffic from x.x.x.1 is taking a different path than x.x.x.2 likely because of a load balancing technique which has some dependency on source ip. I’ve posted the issue in Google’s issue tracker. Thanks for the help! On May 23, 2014, at 10:57 AM, Scott Berkman <scott@sberkman.net> wrote:
Check out this page and the link from there to the Google Public DNS User Group or the Issue Tracker for reporting issues:
https://developers.google.com/speed/public-dns/docs/using?csw=1#troubleshoot...
Hope that helps,
-Scott
On 05/23/2014 03:31 AM, Blake McKeeby wrote:
I have a /24 in an Internap colo and use Google Resolver 8.8.8.8 on all my machines. Google will not consistently respond to RDNS lookups from source IP X.X.X.1 but will respond consistently if I change the IP address of the machine to X.X.X.2. I have proven the DNS response is never returned using tcpdump. It's positively not a local networking issue as changing my resolver to 4.2.2.2 (Level 3) while the machine uses X.X.X.1, the RDNS responses arrive without fail.
Has anyone else seen this sort of selective response by Google? Do they maintain some sort of black list?
_______________________________________________ Outages mailing list Outages@outages.org https://puck.nether.net/mailman/listinfo/outages
participants (5)
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Blake McKeeby -
Eric Henson -
Roland Dobbins -
Scott Berkman -
Stephane Bortzmeyer