> Within 5 minutes, one server would not accept new remote connections. I > could log in fine w/ psql locally. This is pretty bizarre ... offhand I would not have thought that the postmaster depended on DNS service at all. Were you maybe using DNS names instead of IP addresses in pg_hba.conf? What exactly does "would not accept" mean --- what was the exact error message, and was there anything in the postmaster log?
I'm using only IP addresses in pg_hba.conf.
There was nothing in the postmaster log indicating a problem.
The only thing I saw strange was multiple postmasters spawning and disappearing.
The errors I got in the JDBC drivers was the connection pool timing out trying to get a connection, so it's possible they were working, just taking horribly long to connect. Timeouts for Nagios monitoring PG was 10 seconds; pools were 20 seconds. In three years, I've probably seen 3 time outs. :)