Error Executing Database Query. Communications link failure

[John_Sieber]

I recently switched the firewall that sits in front of my MySql database that my ColdFusion based site connects to. The previous firewall was a GBAdmin Gnatbox and I now have a SonicWall TZ210 in its place. I configured the NAT properties and firewall access according to the instructions and when I test the connection it works like before. I'm now seeing several of the following errors throughout the day with pages that connect to this remote datasource:

Error Executing Database Query. Communications link failure The last packet successfully received from the server was 957,562 milliseconds ago. The last packet sent successfully to the server was 958,467 milliseconds ago.
The error occurred on line 237.

It seems like it is possibly trying to use an older connection that may have timed out at the firewall level? Hoping someone on the forum has experienced this before and has some ideas on how to prevent the issue. I'm not sure if I should be looking at the jdbc driver configuration in the ColdFusion administrator, my MySql configuration, or setting for the firewall to stop this error from happening. Any advice or input would be greatly appreciated.

[-__cfSearching__-]

If you have not already, search the forums. There are several threads about MySQL "Communications link failure" errors that might apply, such as

http://forums.adobe.com/thread/773108  (see responses by Steven Erat).

Message was edited by: -==cfSearching==-

[John_Sieber]

Thanks for passing along the link. I checked it out and added a Validation Query of "Select 1" to my datasource options to see if it will resolve the problem. The site only started getting these errors after replacing the firewall, so it seems that the firewall is ending the connections possibly due to inactivity before ColdFusion is ending them. I hope that the validation query will resolve the issue, though it would be great if I could tune the firewall to not end these connections as quickly as it is.