Web Hosting Talk : Web Hosting Main Forums : Hosting Security and Technology : unusual DNS problem

[varunbihani]

We are hosting around 50 websites on Linux dedicated server. For last few months, we are facing an unusual problem with the server and ISP.
after every 3-4 days, our sites stop rendering on some geographical locations but works fine at other locations.
I contacted my internet provider and he said that there is problem with your server
s DNS records and when I contacted my server guys, they said that the problem is with your ISPs DNS records..
I am not able to comprehend what the exact problem is.

i appreciate any sort of help..
Thanks

[sailorFred]

Try http://dnsreport.com/ and see if there are any problems reported.

[varunbihani]

Site Name: www.galaxyweblinks.com

I tried this website on dnsreport.com on 2 machines (each having different DNS IP from local internet provider) on one machine it is working and on other it is not.
but the reports on dnsreport.com is same on both machines.

Can you please check the report on dnsreport.com and make me understand that?

Thanks

[sailorFred]

Looks like you've got some extras, starting with your name servers at your registrar:

Your NS records at the parent servers are:

ns1.galaxyweblinks.com. [72.18.195.161] [TTL=172800] [US]
ns1.machineryhouse.com. [72.18.195.161] [TTL=172800] [US]
ns2.galaxyweblinks.com. [72.18.195.162] [TTL=172800] [US]
ns2.machineryhouse.com. [72.18.195.162] [TTL=172800] [US]

However, the zone only shows two:

galaxyweblinks.com. 38400 IN NS ns2.machineryhouse.com.
galaxyweblinks.com. 38400 IN NS ns1.machineryhouse.com.

If you're going to maintain machineryhouse.com, you can drop the galaxyweblinks.com ones from the registrar. Or you can drop the cross-domain machineryhouse.com ones.

This part isn't critical, though, since all four (really two) servers return the same information.

The next part, where you have both an A record and a CNAME for ns*.galaxyweblinks.com are more likely to be what's causing your problems:

ns1.galaxyweblinks.com. 38041 IN CNAME galaxyweblinks.com.
galaxyweblinks.com. 38042 IN A 72.18.195.161

You've not supposed to have both a CNAME and an A record with the same name. Drop your CNAMEs.

The part about open nameservers is a complaint just about all CPanel servers get. It's not critical, but it would be good to fix.

[varunbihani]

But how is this related to the problem that I am facing? sites open at some places and not at other?
Can you suggest a possible solution to resolve it?

Thanks a ton for ur help!!

[sailorFred]

Fix your dnsreport problems first. The CNAME may be confusing things.

It looks like you've got your glue mismatched now, according to it.

ns2.machineryhouse.com.:
Parent server (m.gtld-servers.net) says A record is 72.18.195.162, but
authoritative DNS server (72.18.195.161) says it is 72.18.195.161
ns2.machineryhouse.com.:
Parent server (m.gtld-servers.net) says A record is 72.18.195.162, but
authoritative DNS server (72.18.195.161) says it is 72.18.195.161
ns2.machineryhouse.com.:
Parent server (m.gtld-servers.net) says A record is 72.18.195.162, but
authoritative DNS server (72.18.195.162) says it is 72.18.195.161
ns2.machineryhouse.com.:
Parent server (m.gtld-servers.net) says A record is 72.18.195.162, but
authoritative DNS server (72.18.195.162) says it is 72.18.195.161

[varunbihani]

what do u mean by mismatched? can u elaborate?.. thanks for ur help

[brianoz]

You need to have the nameservers you gave the registrar for the domain (in your domain settings page) be the SAME as the ones you have defined on your server.

Also, you need to ensure their IPs are the same, both at the registrar and in the zone.

Just study the dnsreport.com output carefully and follow the instructions. If that doesn't make sense ask someone to fix it for you (or read lots of wikipedia entries!!).

[varunbihani]

can you fix it for me?

[Bilco105]

dnsreport.com is your friend