If I leave SQL Relay idle for a long time, then come back and try to use it, my program gets hung or I get a low level TCP error from the database. What does that mean?
If you are running SQL Relay on one machine and the database on a seperate machine, and there is a firewall between the two machines, and no queries have been run in a while, the firewall may “close” the connection between SQL Relay and the database by discarding any packets that it receives from either. The firewall does not send “close packets” to either SQL Relay or the database, so SQL Relay thinks it’s still connected to the database, but when it sends a query, the firewall discards it. Some database client API’s catch this condition and return an obscure error but many do not, they just hang silently forever. Cisco PIX firewalls are known to cause this problem. Others may as well. Allegedly, an IOS upgrade will solve the problem for Cisco PIX firewalls, but I don’t know what version you have to upgrade to. Another solution is to turn off the time out. Yet another solution is to set up a cron job that runs a query periodically and keeps the connection from timing out. You could al
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