Hi John, I use wackamole (http://www.backhand.org/wackamole/) on my (2) front end servers with 6 IP addresses doing Round Robin (RR) DNS.
This is suffichent for loadbalencing the light (HTML / IMAGE only) front end. I had a issue with this once, it got the IP address allocation confused, but otherwise it's been running fine for a year. The front end machines proxy pass to a backend App (mod_perl) server, they do this by name e.g. backend-server, we then have a script that monitors the backend-server and alters the /etc/resolv.conf file if server 1 goes down and alters the ip address to our second machine. Our second machine is actually the DB machine so this is just an emergency fall back until the apps server can be brought up again. Thankfully I've never had to test this in anger! Leo more info: front ends run debian on standard compaq rack mount servers backend 2 Sun Solaris boxes, 1 with mod_perl other with MySQL traffic: 4 / mill pages a month, 50 / 60 hits a second peak Lots and lots of cacheing on the app and indexes on the DB.
