You are correct, resolve.conf does list my isp's dns 250.171.3.65 which
is qwest. The internal windows workstations also point o the isp's dns
server.
Can I setup a cashing dns server on the mail server itself??
Absolutely. Assuming that none is running already:
#> netstat -l | grep -e "domain" -e "54"
Should return no results. Now, there are many opinions out there
regarding what caching name server to use. I think the easiest here
would be BIND. A little bulky, but easily maintained and installed
via YUM. Assuming nothing funky with your install, the following
should work fine. (you probably have one or many of these installed
already)
#> yum install bind bind-utils bind-devel bind-libs caching-nameserver
#> /etc/init.d/named start
#> netstat -l | grep -e "domain" -e "54"
Should now show something like:
~]# netstat -l | grep -e "domain" -e "54"
tcp 0 0 localhost:domain *:* LISTEN
udp 0 0 localhost:domain *:* LISTEN
Now double check that it works:
#> dig @127.0.0.1 yahoo.com
If you get a result with Yahoo's IP address info, go ahead and make
your server use your new caching name server.
Edit /etc/resolv.conf and add "nameserver 127.0.0.1" to the **TOP** of
the list. Leave your ISP's DNS server there just for good measure -
you should always have more than one caching DNS server for
redundancy. It should now look something like:
#/etc/resolv.conf
nameserver 127.0.0.1
nameserver 250.171.3.65
search yourdomainname.com
Feel free to restart your mail server processes if you like, but most
should start seeing your new name server right away.
PS: I just wanted to say thanks to everyone who has helped me so far.
No problem. I just hope it helps. I'm running Qmail right now in an
ISP setup and had nasty issue about six months ago. Got hit with a
double whammy. A bad DNS cache, and a RBL provider timing out and
providing poor performance. Gave me similar symptoms.
-Ken
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