So after things appear to be working again, DOUBLE-CHECK that Postgres in particular is started properly (if it is, it'll appear in ps aux| grep postgr and you'll see its processes along with probably some users connections that already contacted the database). As said, double-check this as Postgres is known, in our setup at least, to need one, two or more restarts before it really starts properly.
ps aux | egrep 'postmaste()r' > /dev/null || echo 'Postgres not running!'
After Postgres, restart domtool-server (it uses Postgres).
Do a test configuration of a domain with domtool (doesn't matter how simple it is) to ensure that all domtool servers are working.
1. Other systems
Since Deleuze is the main server, its period of unavailability will affect other machines. In specific, the web server needs to be restarted, or even rebooted if SSH stops taking logins (this happened Jan 20, 2010 outage).
Also, restart domtool-slave processes on all machines that have it.
Also, on last Deleuze unavailability, DNS on outpost stopped receiving updates, it needed a service restart (domtool and/or bind9).
So the bottom line is, after rebooting deleuze, re-check everything 
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