TCP With Firewall

What happened the next day

Sure enough, the pattern repeated itself the next morning. Application servers locked up tight as a drum, with the threads inside the JDBC driver.

Absence of traffic

This time, we were able to look at traffic on the databases’ network, but found nothing at all. The utter absence of traffic on that side of the firewall was like Sherlock Holmes’ dog that didn’t bark in the night—the absence of activity was the biggest clue.

Decomposition of the server

We had a hypothesis. Quick decompilation of the ...