DNS Resolving issues. So for related just to Cox. But could be larger.

Mark Keymer mark at viviotech.net
Wed Mar 5 04:40:37 UTC 2014

Hi Everyone,

So I have a client who moved a domain specifically periodforgood.com to 
a new VPS with our company.

DNS has been updated and the TTL time is 4 hours so things should all be 
updated but something might still be wrong. Looking for help / 
confirmation that things look good. And better yet if someone from Cox 
and take a look.

Our client uses Cox for there home internet and sometimes the domain 
resolves and sometimes it does not. We found they have the following 
IP's in Cox's network that are being used to resolve domains.

After doing many nslookups via a remote session to there computer we 
found that the top 2 IP's never resolve the periodforgood.com domain and 
we found that the third one will about 20%-40% of the time resolve it.

We have gone to several DNS testing tools and all seems to be in order. 
If you dig or nslookup directly to the DNS servers that are used for the 
domain it seems to always respond.

I admit I might just be overlooking something myself and will feel dumb 
once someone points it out to me. But if you can point it out to me that 
would be great!

Also note that it looks like those DNS resolvers are blocked from 
outside lookups which is good. So maybe someone with some eyeballs 
inside or otherwise can help out?


Mark Keymer
Vivio Technologies

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