Is the Win2K DNS client a cache? 1

[euston]

Hi guys,

Windows 2000 has a DNS client service. Is it a DNS cache and, if so, is it configurable? For example, can the maximum TTL be set?

 

[John Lewis]

What you are seeing is a caching DNS resolver service. You can edit the registry to configure some goodies. Of course, you know, if you do this, your computer will blow up. If you don't know what your doing, don't even think about touching the registry. Having said that . . .

HKLM\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters\MaxCacheEntryTtlLimit sets the maximum TTL, if a lower value is specified by the DNS server that is used instead.

The service also caches negative responses.
HKLM\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters\NegativeCacheTime sets the timeout for negative responses. I don't think that one is there by default, but the value indicate the number of seconds the negative response is held. I think the default is 300 seconds.

 

[euston]

Thanks mhkwood. I have had a peep inside the registry and the settings appear to be quite reasonable. Max TTL is one day and the number of entries are 211 (why not 212? 200????). What an arbitrary figure! Thanks for the advice. I shall not blow up my computer on this occasion.