[PATCH] mkinitrd rescue mode

[Jeffrey Layton]

On Mon, 2005-06-06 at 14:06 -0400, Peter Jones wrote:
> How often is that a real problem?  I don't think I've seen any
> significant number of bug reports on this in recent memory.

That's just a "for instance". Most of them aren't actual bugs, and so
you won't see BZ tickets on them.

Problems booting after kernel upgrades are common, however. We deal with
them on a daily basis in production support. The problem for us is that
there is virtually no simple way to troubleshoot the case where the
rootfs isn't getting mounted for some reason, the switchroot fails, and
the kernel panics. The most helpful messages telling us what the problem
is usually have scrolled off the screen. We generally have to fix this
based on experience and guesswork.

You can have the user set up a serial console, but users who are savvy
enough to figure out how to do that are generally able to troubleshoot
their own booting problems. Being able to tell a user to add "rescue" to
the command line and then to walk them through some commands (like
dmesg) to try to determine the problem would be very helpful for a
number of different reasons. It would also give people the ability to
try to rescue corrupted root filesystems without needing special
infrastructure (like a PXE server) and without having to physically be
near the machine (with a CD boot).

Since we're discussing this, I posted a proposed patch this morning to
nash to clean out the initramfs prior to the switchroot:

https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=159636

If nash is able to clean out the initramfs before switching the root, is
there any reason _not_ to have some useful tools in it?

-- 
Jeffrey Layton <jlayton at redhat.com>