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progjm

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DNS Cache

If you have 3 DNS entries and the top two fail, how long will it take for the top address to be tried again? Is there a way to adjust this besides rebooting?

Thanks
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Adrian Cantrill
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in windows 7 ?
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progjm

ASKER

Yes
I believe that from windows xp service pack 2 and onwards there is a timeout method. If a primary server doesnt respond it is marked as 'dead' for 15 minutes during which time the secondary is consulted. After the 15 minutes it tries the primary again. This can be adjusted with a reg change - i can find it if you want, ive never had the need to change.
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I was trying to find it also and couldn't, probably just blind lol
Are you are talking about the local DNS cache?.. if you execute IPCONFIG /flushdns from a command prompt, it will purge the local DNS cache and force the client to obtain a fresh address from the DNS server.  The time the DNS entry will remain in the local DNS cache is set by the TTL value which is set at the DNS server.

To see all the entries in the local DNS cache you can type IPCONFIG /displaydns from a command prompt.  Then ... if you just want to check a specific entry... use the IP or URL from the list that you want to test.

Here is a link to some additional info that may address your question further:
http://www.helpwithwindows.com/WindowsXP/tune-24.html
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ASKER

flushdns didnt work, only rebooting or disabling the network interface. It did however start using the first address after some time but I am trying to find out what that time is. The addresses are statically assigned and dont recieve any data from /displaydns. I appreciate the link, good info to try there
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Adrian Cantrill
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