Note that it is desirable and possible to use multiple plexes, each containing one replica of the root file system. The bootstrap process will only use one replica for finding the bootstrap and all boot files, until the kernel mounts the root file system. Each single subdisk within these plexes needs its own
<literal>a
</literal> partition illusion, for the respective device to be bootable. It is not strictly needed that each of these faked
<literal>a
</literal> partitions is located at the same offset within its device, compared with other devices containing plexes of the root volume. However, it is probably a good idea to create the
<filename>vinum
</filename> volumes that way so the resulting mirrored devices are symmetric, to avoid confusion.