Re: "Run fsck manually"..?

[Greg Wooledge <wooledg@eeg.ccf.org>]

On Wed, Feb 03, 2021 at 02:06:04PM -0600, David Wright wrote:
> >From foo/main/init where foo is
> $ unmkinitramfs /boot/initrd.img foo/

Interesting....  I used locate --regex to find where this is coming
from, and it seems there's a copy in /usr/share/initramfs-tools/init
which I'm guessing is what gets installed as init inside the initrd.

/usr/share/initramfs-tools/init is from the initramfs-tools-core
package which appears to come from Debian itself (according to
the copyright file), having been forked from Ubuntu's version.

A google search for "linux fsck.mode=force" led me indirectly to the
systemd-fsck man page.  This one tells me that fsck.mode= is an option
supported by systemd-fsck with the values auto, force or skip.  Debian's
/usr/share/initramfs-tools/init script appears to be using a superset
of these values, including your forcefsck alias.

Putting these clues all together is tricky for me because nothing is
really spelled out clearly.  Near as I can manage to guess, Debian's
initrd init script parses the kernel command line and looks for these
fsck-ish options, applies them during the initrd stage, and then...
then, I don't know what happens.

There is still no clear end-user-comprehensible documentation that says
how to make fsck happen on the next boot.

> > What is the "normal mechanism"?  Where is it documented?
> 
> https://www.gnu.org/software/grub/manual/grub/grub.html

(I told you guys how my email is being mangled....)

> I'm guessing the comment is a signature. §15.2 outlines the grubenv
> method. As Stefan mentioned, grubenv is designed to remain static,
> and grub-editenv carefully alters its contents. Configuring Grub
> uses /etc/grub.d/00_header and the variables in /etc/default/grub to
> write the code at the top of /boot/grub/grub.cfg for juggling the
> boot selection.
> 
> You start all this off by editing /etc/default/grub: GRUB_DEFAULT=0 →
> GRUB_DEFAULT=saved    and running   grub-set-default 0. Then:
> 
> $ head -c 72 /boot/grub/grubenv ; echo
> # GRUB Environment Block
> saved_entry=0
> #################################
> $ 
> 
> # grub-reboot 'fsck>fsck'

At this point I give up.  I don't know where this "fsck>fsck" argument
comes from or how you use it.  It's definitely not in the grub-reboot
man page.