I recently upgraded to Big Sur and found I had to upgrade Fusion to version 12 as well. I have a Debian Linux client.

Ever since then, my bridged network has been behaving strangely. Viewing Google pages in the browser seems to work, but every other page comes up blank. fetchmail can't connect to my mail server. My NAS can start an rsync backup to my client, but it always eventually dies with:

Connection to 192.168.50.4 closed by remote host.
rsync: connection unexpectedly closed (653017239 bytes received so far) [receiver]
rsync error: error in rsync protocol data stream (code 12) at io.c(605) [receiver=3.0.9]
rsync: connection unexpectedly closed (58 bytes received so far) [generator]
rsync error: unexplained error (code 255) at io.c(605) [generator=3.0.9]

My NAT adapter is working as it always has.

Am I waiting for a Big Sur or Player 12 update that will magically fix bridged networking, or is there some tweaking that is required to fix this?