Recurring problem in root filesystem

[Guy Harris]

>> >Try running fsck on the *unmounted* root filesystem,
>> Try unmounting the root filesystem first.  Good luck....
>
>Wait a minute. Can't you chroot() to another filesystem, then remount
>the original root below the new one?

Well, for one thing, that doesn't unmount the root file system, it
remounts it.

For another, 4.3BSD, System V Release 3, and probably most if not all
other UNIX systems don't let you mount the same local file system twice.