Re: [squid-users] Reverse DNS Problems and Delays

On Mon, 15 Nov 2010 09:18:18 -0600, "Baird, Josh" <jbaird_at_follett.com>
wrote:
> Should I encounter long delays when accessing a HTTP site via IP (not
> FQDN/friendly name/etc) that does not have a valid reverse DNS record?
> I am encountering an issue where it takes 25-30 seconds to access a site
> that does not have a valid reverse DNS record. Using Squid 2.6/EL5.
>
> Thanks,
>
> Josh

Depends on what ACLs you are using to control access and the response time
of the DNS resolvers for that IP.
The older Squid releases than 3.1 would perform one lookup for every ACL
test using the rDNS, which could amplify the problem. Ideally Squid and
it's resolver would get a NXDOMAIN record back very quickly for it.

The other alternative is that the link direct to that IP is simply very
bad.

Amos
Received on Mon Nov 15 2010 - 22:48:53 MST