Symptoms: TCP Connections Reset After Idle Period

• Long-running TCP connections (database pools, SSH sessions, message queues) drop after approximately 60 minutes of inactivity.
• Application logs show "Connection reset by peer" or "Broken pipe" errors.
• Connections that have active traffic remain stable indefinitely.
• The problem does not occur when the client and server are on the same subnet.
• Restarting the application temporarily resolves the issue, but it recurs after the next idle period.
• Network monitoring shows no link flaps or interface errors during the resets.
• The issue began after a new firewall was deployed between the application and database tiers.
• Short-lived HTTP connections are unaffected.