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Browse All TopicsWe recently changed our website ISP and have changed our internal DNS to reflect the change in DNS servers for the new ISP. I have flushed the DNS on all servers, reset the cable modem, and reset our router which should clear any DNS cache. The issue is that when we go to our website it will come up with an error from our old isp saying that the website is not available. If I flush the DNS on the user's computer,flush the server DNS caches delete files and cookies on the browser, it will run for a while just fine and then revert to this same error. I am lost as to where this old DNS entry could still be cached. Any help in geeting to the source of this would be most appreciated
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by: NopiusPosted on 2007-05-13 at 19:16:19ID: 19082672
1) Why did you change _internal_ DNS while your Webserver is external? Is it serves also external DNS queries?
2) The issue is that when we go to our website it will come up with an error from our old isp saying that the website is not available.
Try to run 'nslookup yourwebsite' on client's machine, what does it tell (old IP or new IP)?
3) If I flush the DNS on the user's computer,flush the server DNS caches delete files and cookies on the browser, it will run for a while just fine and then revert to this same error. I am lost as to where this old DNS entry could still be cached.
Are you sure that you have _old_ DNS entry when asking for your server (check with nslookup as above)? If yes, than, most likely, your internal DNS servers just forward DNS queries to your ISP's DNS. It typically takes 2 days to propagate DNS when you change it, so your ISP is just caching old entries, just wait for 2 days and try again.
If no (you get new IP address with nslookup), then problem is not in your DNS, may be in some transparent (or non transparent) WEB proxy between you and your website, that is caching old pages, or the problem may be in your new website, that doesn't configured properly and doesn't respond to query.
4) Try to access manually IP address of your new site instead of hostname with telnet command, like:
telnet x.x.x.x 80
GET http://yoursite.com/ HTTP/1.1
Host: yoursite.com
<double enter>
If you see anyu response, than problem is most probably in your DNS, if not - in your Webserver.