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Strange Behavior from Singapore DNS - Printable Version

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Strange Behavior from Singapore DNS - pdibona - 12-31-2013 05:42 AM

Hello,

I realized that I had posted this in the wrong forum area, here is the post in the correct area, I will delete the old post.

I just wanted to report some strange behavior for the DNS attached to the Singapore WPT agent. We use WPT in addition to Keynote for a majority of our web page monitoring and analysis. Our Keynote agent located in Singapore that uses SingTel has had very consistent performance and consistent routing based on the DNS associated with SingTel. Within WebPageTest, about 2/10 Name Resolutions are incorrectly routing to one of our data centers in the US. The remaining 8/10 Name resolutions are correctly being sent to another of our data centers located in the EU area. Has anyone heard of this happening before? Is there anything we can do to fix this? The DNS server in question is located at the IP address: 172.16.0.23.

Thanks in advance for any help you send our way!

Pete


RE: Strange Behavior from Singapore DNS - pmeenan - 01-03-2014 06:17 AM

It's a matter of your CDN's routing logic not working well with DNS requests coming from EC2 and they are having troubles geo-locating the traffic. It's not an issue for AnyCast CDN providers but those that do the geo-locating at the DNS level tend to suffer more. For Keynote it's pretty easy because teh CDN's tend to optimize for them specifically and will actually have gear that is dedicated for serving the Keynote requests (and they make certain the DNS geo-locating works for the Keynote resolvers).

There's nothing that I can really do on my side.


RE: Strange Behavior from Singapore DNS - pdibona - 01-10-2014 06:52 AM

Patrick,

Thank you for your reply, and explanation of things. This has been a big help. I also wanted to thank you for a great tool, the more I learn about it the more I realize how awesome it is, so thank you!

Pete