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DNS just stopped working out of the blue - no errors in log! Entire network down

Posted on 2008-06-11
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Last Modified: 2010-04-07
2003 server single domain. All has been configured and working properly for many, many months. This afternoon, we all of the sudden lost the ability to resolve external names. Internal IPs no problem. Checked error logs for system and DNS on server - nothing, absolutely nothing. Checked for SOA and reverse lookup records - present. Stopped and restart services - event log says everything fine. But we cannot resolve outside names. Now down for two hours. Tried to read MS troubleshooting knowledgebase using our external wireless but nothing obvious. Really starting to pull me hair out. All suggestions welcome, logical, in order, and hopefully include a sure-fire "if all else fails try this" would be great.
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Question by:214-042308
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by:debuggerau
ID: 21765243
what is your ISP dns server?

Can you nslookup a internet address?

just type in 'nslookup' and press ENTER.
then type in 'server <isp_ipaddress>'

Then try a internet address and see if it finds it, if not post the results.
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Jay_Jay70 earned 500 total points
ID: 21765383
remove the forwarder address from DNS, let DNS fall back on root hints, flush your DNS cache and you should be right

Unless of course you have blocked port 53 on your firewall :)
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by:manu4u
ID: 21767847

First of all, make sure that you can ping external IPs , for example you are able to reach your ISP DNS server.

Then, ipconfig /flushdns command would clear the cache, however you have restarted the DNS server service, right? .. So, it's fine.

Make sure that there is no IP CONFLICT and your FIREWALL configuration is nt changed.
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