The server is waiting for tcp/ip disconnect, which is never coming because the firewall eats this, resulting in backends waiting to death. Again: you'll have to request your sysadmin to fix the firewall, at least on that pgsql port for internal use. Timeouts simply don't make sense here. You won't have DOS attacks internally, I hope (if you do, locate the aggressor, and eliminate him).
The architecture just doesn't fit here - it's two LANs connected over a VLAN, so the firewall is between us and the open internet, even though the PG-server is in it's own LAN. I can not fix the firewall, it's not in my jurisdiction and I cannot take it there. Changing firewall-settings is simply not an option for me. I see that there's no way that you would consider implementing a keep-alive feature. That's fine, I shall have to live with the issue. Sorry to have asked in the first place. ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html