I recently upgraded from 9.1(4) to 9.6(2). Once I performed the upgrade there were traffic issues, "SYN TIMEOUT".
After much troubleshooting, I downgraded back to ASA 9.1(4). As soon as the downgrade was complete, user traffic was working again, and no SYN TIMEOUTS. I am not sure why it was getting timeouts, I did not see anything in the release notes before I upgraded that would have caused those errors.
I know I will need to upgrade the ASA, is there a recommended version to upgrade to without jumping to 9.6 again?
