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reason behind having to flush you DNS cache?

Community Veteran
Posts: 3,181
Thanks: 19
Fixes: 2
Registered: 31-07-2007

reason behind having to flush you DNS cache?

In the last month and a bit I've noticed having to do that on a regular basis for a problem site www.adsltech.com . It has a problematic Host, but I can normally get the IP to do a ping trace and check if port 80 is open. But lately can't check the IP as the nslookup fails, so having to flush the cache.

So is there a possible cause on my end I can fix to help reduce this, or nothing I can do about it?

Using win2kPro + sp4
Router is manually set for PN ADSL DNS servers
Unvalued customer since 2001 funding cheap internet for others / DSL/Fibre house move 24 month regrade from 8th May 2017
3 REPLIES
N/A

reason behind having to flush you DNS cache?

XP remembers negative (DNS unable to resolve) entries for a few minutes. As long as that negative entry sits in your DNS cache, your box will continue to give you a cannot find server error. By cleaning out your DNS cache, you can fix this problem.

If you wish to stop XP from placing negative entries into cache, you can make this change in your registry.

1. Goto HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters
2. Build a new DWORD value called NegativeCacheTime and give it a value of 0

I believe the default time is 5 minutes. I always use zero for my default time, but I think the value above is in seconds. So if you only want to save them for 1 minute, then I am assuming you would change that value to 60.
N/A

reason behind having to flush you DNS cache?

Loads of good articles and tweaks on this here

http://www.speedguide.net/read_articles.php?id=158
pcorker
Grafter
Posts: 309
Registered: 05-09-2007

reason behind having to flush you DNS cache?

Useful info - thanks, guys!
Pat.