Here is the process we are using to setup our Gateway:

1. Install CentOS 5.1 which is the standard linux operating system for the gateway. 
2. Turn off all unnecessary services.
3. Enable automatic security updates (e.g. @midnight yum update in crontab)
4. Install the icom gateway software
5. Install the community fixes to the icom software and any programatic dependencies for the community software
6. Do convenience fixes to the server
7. Register the gateway on the D-Star Users page.
8. Put the gateway into test mode and test it locally without repeater hardware
9. Put the gateway into test mode and test it with the repeater hardware
10. On the air test