What about this pinned post? ‼ READ FIRST - Before Posting in Get Help
It has a list specifically for connection issues.
However, if your "lan port" was locking up, then the diag tool on 8081 would also not work. So your problem actually sounds like the mian platform is crashing, not the ethernet port itself.
If you think it was caused by a platform update use the diagnostics tool to roll back the firmware. If you find that solves the problem report back because the devs would definitely like to know so they can look into it further.
