On 8/4/19 7:26 PM, Grant Taylor wrote:
I am also using a bit of a hack that I think could be (re)used to allow
/usr being a separate file system without /requiring/ an initramfs /
initrd. (I'll reply in another email with details to avoid polluting
this thread.)
I think that a variation of a technique I'm using for LUKS encrypted
/home on a VPS could be used to allow booting without an initramfs /
initrd while maintaining a separate /usr file system.
The problem is that /bin & /sbin would be symbolic links to /usr/bin &
/usr/sbin. So, any commands that would be needed to mount the /usr file
system would need to be directly accessible in /bin & /sbin paths, or
indirectly accessible in /usr/bin & /usr/sbin.
IMHO this is a whopper of a hack.
Create the bin and sbin directories inside of the /usr directory that is
the mount point so that they are on the underlying file system that /usr
is mounted over top of. Then copy the needed binaries to the /usr/bin &
/usr/sbin directories on the underlying file system. That way,
/sbin/fsck -> /usr/sbin/fsck still exists even before the real /usr is
mounted.
I did say this is a whopper of a hack.
It's trivial to access these directories even when the normal / full
/usr is mounted.
1) mkdir /mnt/root-underlay
2) mount -o bind / /mnt/root-underlay
3) ls /mnt/root-underlay/bin /mnt/root-underlay/sbin
This "technique" / "trick" / "hack" works because the /bin & /sbin
""directories are sym-links to the /usr/bin & /usr/sbin directories.
There is nothing that means that the contents of (/usr)/(s)bin can't
change from one command invocation to another. The /(s)bin sym-links
just need to point to a valid directory. They can easily be on the
root-underlay file system that /usr gets mounted on top of.
--
Grant. . . .
unix || die
