sudo drbdadm -f primary r0
I would get this error:
0: State change failed: (-2) Need access to UpToDate data
Command 'drbdsetup 0 primary' terminated with exit code 17
sudo drbdadm -f primary r0
0: State change failed: (-2) Need access to UpToDate data
Command 'drbdsetup 0 primary' terminated with exit code 17