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smp_86112's avatar
smp_86112
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Mar 06, 2014

Testing GTM topology results

I was wondering what resources people use to test the effect of GTM-topology load-balancing on Internet-based LDNS servers? I need a way to submit a DNS query that will reach my GTM from a geographically-known DNS server. I've googled this quite a bit, but haven't found a great resource yet which I find a little surprising. I was wondering how other people test their topology records?

 

    • smp_86112's avatar
      smp_86112
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      The problem with the two web sites you referred to are that they don't give you any mechanism to submit a query from a geographically-known DNS server. In fact, it doesn't even tell you where the LDNS server that submitted the query is located - I have to figure that out on my own.
  • As far as I can tell, these tools don't tell you which states/countries/regions their resolvers are located in.

     

    I've also been looking for a way to validate GTM topology effectiveness and have found nothing.

     

    • smp_86112's avatar
      smp_86112
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      See https://www.whatsmydns.net It's the only half-decent site I've found so far. I'm hoping someone else has already tackled this problem.
  • Of course, shortly after submitting this question I found this which is pretty much exactly what I am looking for.

     

    https://www.whatsmydns.net

     

    The number of DNS servers is pretty limited though, so I'd be interested in seeing what other sites people use to test their topology records.

     

    • smp_86112's avatar
      smp_86112
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      I think the trick is to search for terms related to DNS propogation instead of "geoip". There are quite a few sites that are geared for propogation-type checks, which of course can also be used for geolocation tests too :] Here's another one I found: http://viewdns.info/propagation/
  • Not sure what your requirements are, but Pingdom.com has geographically distributed monitoring sites (list of source IP address is available from Pingdom). If you set up Pingdom to monitor a URL, you will see each monitoring request come from the respective geo location.

     

    • smp_86112's avatar
      smp_86112
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      > Not sure what your requirements are I am looking for a (free) way to submit a DNS query for my WideIP to a DNS server which is known to be in Germany. Or Brazil. Or Canada. Or Japan. Or, or, or... That's the only way I'll know for certain how my GTM will process its topology records. I don't have DNS servers in all these geographic regions, so I have no way to test them other than to submit the query from someone else's DNS server. I think the service you referred to would probably work, but it's a more formal service than what I'm looking for. I'm basically just looking for a free web tool. Thanks for the response though.
    • devop_308539's avatar
      devop_308539
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      Very helpful website - the DNS propogation website. If you are having trouble in one area or region, like you stated, you can use any online load testing site to test specific regions. Load Impact is one like the other person provided. I use LoadView since I can do some testing for free and I can choose the locations I wish to test in. For example, I want to test in Australia, scale up to 10 or 1,000 users at once and record it so I can play it back and see what is actually going on, then run that script every minute for the next week and only send me the high level concerns. Not sure if that would be helpful or not, but you can check them out here: https://www.loadview-testing.com/

       

  • This isn't a web tool, but here is a list of public DNS servers by geographic location:

     http://wiki.opennicproject.org/Tier2
    

    With nslookup (or dig) you can set your DNS server: "server x.x.x.x" and direct a query to a DNS server of your choice.

    • smp_86112's avatar
      smp_86112
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      Yep, this is also great resource. Thanks very much for the reference.