Plex Server Crashes after BigSur update

Are you getting a kernel panic that requires the computer to be restarted?

If so, are you also using any Network Extensions?

If that’s the case for you, the quick solution is to disable the Plex DLNA server and then check for updates to the Network Extensions. Read the linked thread for more info.

defaults write com.plexapp.plexmediaserver DlnaEnabled 0