I have been using chroot recently to do some compiling in a different
environment and distro. Sometimes, I forget to do mount -t proc
none /mnt/chroot/proc before doing the chroot.

Most everything works OK when compiling. Only failings I have seen are
the failure of certain programs to locate the correct kernel source when
compiling and mkinitrd reports /proc not found.

My question is: Exactly what is the reason for mounting a local copy
of /proc prior to chrooting? Some FAQ show proc being mounted AFTER
chrooting:

# mount /dev/hda## /mnt/chroot
# chroot /mnt/chroot
# mount -t proc none /proc

as opposed to:

# mount /dev/hda## /mnt/chroot
# mount -t proc none /mnt/chroot/proc
# chroot /mnt/chroot

Are these two identical? Any clarification or links to clear FAQ are
appreciated!

--
Peter

Peter wrote:
> I have been using chroot recently to do some compiling in a different
> environment and distro. Sometimes, I forget to do mount -t proc
> none /mnt/chroot/proc before doing the chroot.
>
> Most everything works OK when compiling. Only failings I have seen are
> the failure of certain programs to locate the correct kernel source when
> compiling and mkinitrd reports /proc not found.
>
> My question is: Exactly what is the reason for mounting a local copy
> of /proc prior to chrooting? Some FAQ show proc being mounted AFTER
> chrooting:
>
> # mount /dev/hda## /mnt/chroot
> # chroot /mnt/chroot
> # mount -t proc none /proc
>
> as opposed to:
>
> # mount /dev/hda## /mnt/chroot
> # mount -t proc none /mnt/chroot/proc
> # chroot /mnt/chroot
>
> Are these two identical? Any clarification or links to clear FAQ are
> appreciated!

I won't try to explain weather or not the two ways might work identical,
but since the proc filesystem is a kernel interface, I would never
chroot without first having mounted the proc fs belonging to the kernel
I'm chroot'ing to.
Everytime I do it the Right Way, it works fine for me.

Usually, I do this when installing Gentoo from a USB disk image, booting
off the cd.
Sometimes, a new netcard (i.e. Broadcom or Intel Gbit on a Dell) is not
supported, so I compile the driver. I'll later emerge the Gentoo driver.

--
Kind regards,
Mogens V.

On Sat, 2006-05-06 at 13:24 +0200, Mogens V. wrote:

snip...

> I won't try to explain weather or not the two ways might work identical,
> but since the proc filesystem is a kernel interface, I would never
> chroot without first having mounted the proc fs belonging to the kernel
> I'm chroot'ing to.
> Everytime I do it the Right Way, it works fine for me.
>
> Usually, I do this when installing Gentoo from a USB disk image, booting
> off the cd.
> Sometimes, a new netcard (i.e. Broadcom or Intel Gbit on a Dell) is not
> supported, so I compile the driver. I'll later emerge the Gentoo driver.
>

So, you're saying
mount -t proc none /mnt/chroot/proc
chroot /mnt/chroot

is the "right" way? When I do it this way, the errors I noted are
absent, which _is_ good!

Thx

--
Peter

Peter wrote:
> On Sat, 2006-05-06 at 13:24 +0200, Mogens V. wrote:
>
>>I won't try to explain weather or not the two ways might work identical,
>>but since the proc filesystem is a kernel interface, I would never
>>chroot without first having mounted the proc fs belonging to the kernel
>>I'm chroot'ing to.
>
> So, you're saying
> mount -t proc none /mnt/chroot/proc
> chroot /mnt/chroot
>
> is the "right" way?

Yup

--
Kind regards,
Mogens V.