1. point all apps in IAD to oltpdb1-1-prod-iad (o2_dbwriter.iad.agkn.net)
   2. point all apps in SJC to db2-1-prod-sjc (o2_dbreader.sjc.agkn.net)
   3. tear down all replication
   4. upgrade slony RPMs on all hosts (slony1-II on postgres, Truviso-slony1-II on truviso)
   5. resubscribe first-order slaves:
          * oltpdb2-1-prod-iad
          * whsedb1-1-prod-iad
          * reportdb1-1-prod-iad
          * db1-1-prod-sjc
   6. point all apps in SJC to db1-1-prod-sjc (o2_dbwriter.sjc.agkn.net)
   7. resubscribe second-order slaves:
          * db2-1-prod-sjc
          * whsedb2-1-prod-sjc
          * reportdb1-1-prod-sjc