Symmetric failover

Description

This directory contains a configuration file setup for symmetric failover. In such a situation, each machine has a virtual address in addition to the real adress. As soon as the partner fails, the second address is activated on the remaining machine.

Such a setup is particularly usefull with proxies or web servers. If you publish both virtual addresses in a DNS server that does round robin DNS, you get a natural load sharing configuration. If one of the servers fails, the other will take over the service from the failed partner.

Installation

After the build is complete, edit the file config in this directory to reflect your setup. The comments on the config file should help you determine the right parameters.

Then run the setup script

    $ sh setup
This creates two directories host1 und host2 containing start/stop scripts named faild, failsh and after the ip addresses in use (4 scripts in each directory). Furthermore, there is a tcl script named after the host. You should copy these files to the target hosts as follows