whonixcheck fail: tor.pid does not exist after upgrade from Whonix 11 to Whonix 12

Support
10

Check…

sudo ifconfig

See if it shows both interfaces.

Did you make any changes to /etc/network/interfaces some time ago such
as for multiple Whonix-Workstations?

(VirtualBox is now also using
/etc/network/interfaces.d/30_non-qubes-whonix.)