Some domains don't resolve.

Sten Carlsen ccc2716 at
Sat Jun 7 08:30:32 UTC 2008

The question as I read it, is if a very small amount of users will 
benefit most from using the cached lookups of a large number of users 
(the whole ISP population) or from having their own independent resolver.

I have that situation here, I first used forward but later switched to 
just resolving. My feeling (I have no statistics) is clearly in favour 
of NOT forwarding. I don't see any speed penalty in real life but got 
rid of some mysterious issues that happened while forwarding and the 
speed seems to be higher.

just my 2¢

Barry Margolin wrote:
> In article <g2aeee$1bb9$1 at>, Kevin Darcy <kcd at> 
> wrote:
>> Barry Margolin wrote:
>>> But if your ISP has 100,000 users of the same caching server, it will be 
>>> cached if any of 1,000 users have accessed it recently.  For any one of 
>>> them, there's only a 0.1% chance that their lookup will be the one that 
>>> has to wait for fetching from the source.
>> And if you have 100,000 users using the same caching server, it's likely 
>> to experience big spikes of activity (e.g. several thousands of queries, 
>> within the course of less than a second), during which time some users 
>> will experience some extra delay in getting their queries resolved.
> Certainly if the nameserver is not engineered to handle the load it's a 
> bad idea to use it as a forwarder.  That's a completely different issue 
> than whether it's useful to share caches via a forwarding hierarchy.

Best regards

Sten Carlsen

No improvements come from shouting:


More information about the bind-users mailing list