> The Load Balancing section of this doc might help: > http://httpd.apache.org/docs/misc/rewriteguide.html > > Just straight apache + mod_rewrite could be the simple solution you > seek. The Proxy Throughput Round-Robin example shows how to add a > script to do mapping as well - could work for your availability > detection requirement.
We've also used mod_rewrite in a lightweight reverse proxy as a stopgap when load balancing hardware was not available. One option for detecting live backend servers is to use the "prg" rewrite map like Paolo says, where a script does some sort of availability check. Another option which we have used is the "rnd" map where a server is selected randomly from a flat file, where that file can be kept updated by an external (non-Apache) process like a cron job that checks backend server availability (mod_rewrite notices on-the-fly when that file has changed). Larry Leszczynski [EMAIL PROTECTED]
