[squid-users] DNS Caching

Good morning, afternoon, and good evening.

Quick question... Can someone explain to me HOW does squid cache DNS, and
how to avoid it?

We switch between a couple of live servers via DNS, bind9 and squid 2.5....
Uhm... We have the following:

webserver1 IN 86400 A <IP>
webserver2 IN 86400 A <IP>
webserver3 IN 86400 A <IP>
www IN 1 CNAME webserverX

Now, bind9 runs with query logging as well. Squid uses the correct
nameserver for queries (as indicated by cache.log), but named's query log,
indicates NO queries being made from the Squid IP address (Bind + Squid on
the same server).

I've even changed all the below to 1 second TTL
negative_ttl, positive_dns_ttl, and negative_dns_ttl.

From what I can see, I have no 53/UDP traffic from Squid to our nameserver,
bind indicates no queryies from squid for the URLs that we do the switching
from, and we did already have a situation now where we altered the www CNAME
record to point to a different server, and squid did NOT pick this up,
untill after I restarted squid.

What's my solution here???? Surely, Squid MUST honour the DNS TTL on the
CNAME?????? Why it is not honouring the positive/negative_dns_ttl
either???? How can I avoid squid to cache DNS completely???

Thanks,
Chris.
Received on Wed Sep 07 2005 - 03:54:57 MDT