Comment 1 for bug 1362248

FYI, I'm planning on tackling redundancy manually for now. Something like this:

1. add a postgresql unit (for the failover DB);
2. set up a second reviewboard service related to the failover DB;
3. set up replication from the primary DB to the failover one;
4. in the event the primary goes down, update DNS/reverse-proxy to point to the failover RB instance.