--modern
Equivalent to --epoch=1.
--epoch
This accepts an integer value in the range [0-1], inclusive. The default is zero for compatibility.
When set to 1, the command will skip adding a number of toplevel "API filesystems" such as /proc to
the toplevel of the physical root. These should be unnecessary, as they should only be mounted in the
final deployment root. The main exception is /boot, which may need to be mounted in some setups
before the target root.
Epoch 2 is the same as 1, except that the toplevel ostree directory is mode 0700, denying access from
unprivileged code. This is a new recommended best practice as it avoids access to old configuration
files in /etc in previous deployments, as well as potentially old setuid binaries in /ostree/repo.