Can I change the device of the "/" mount point at boot time.

[Mike Meyer]

On Tue, 15 Jul 2008 00:48:42 +0530
"Tapan Chaudhari" <tapan.list at gmail.com> wrote:

> This is not exactly what I wanted. I will try to elaborate myself.
> I am creating my own device which will act as a new boot slice which must be
> mounted as '/'. New device will process i/o calls and then redirect the i/o
> calls to original device of '/'. Now since I cannot unmount '/' and mount it
> again with my new device while system is running, I will have to find a way
> to tell kernel to mount my new device as '/' from next time onwards it
> boots.
> does anyone have suggestions on this?

That's pretty much exactly what vfs.root.mountfrom does. Edit
/boot/loader.conf to add a line:

vfs.root_mountfrom="fstype:devicespec"

and you're good to go. The kernel will boot from your default root
partition, then remount root using the value of that variable. I.e. -
I set mine to "zfs:internal/root" to boot my system to a zfs root.

  <mike
-- 
Mike Meyer <mwm at mired.org>		http://www.mired.org/consulting.html
Independent Network/Unix/Perforce consultant, email for more information.

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