SonicWall NSA 250M high memory usage
If you've upgraded your NSA 250M to 5.9.x you may notice the memory usage constantly high and sometimes being unable to log into the management GUI.
This usually occurs when the cpu core 0 is constantly high, and caused by a setting change.
Log into the NSA 250M and navigate to Firewall Settings -> Flood Protection. You will probably see under TCP Settings, an option called Enforce strict TCP compliance with FRC 793, RFC 1122 and RFC 1323 which will be enabled (ticked). Untick this option, and click on Accept to apply the change. This should help resolve the problem.