I've run into this problem before: how do I empty the DNS cache in Linux?

I've changed a record in my DNS server, and ping still insists that the
server is at the old address.   However, if I point nslookup directly at
any/all of the DNS servers, I get the correct (new) address.

I've tried touch'ing /etc/resolv.conf and /etc/nsswitch.conf.  I've
poked around in /var looking for the file that the DNS client uses to
store the database.  It has to be a file, because the last time I ran
into this problem, a reboot wouldn't encourage ping or any of the other
tools I tried to actually query the server and get the new record...

Any suggestions?

Thanks,
-Luke

-- 
Luke Scharf, Systems Administrator
Virginia Tech Aerospace and Ocean Engineering