Booting problem from last week

[Robin Green]

On Tue, 03 May 2005 23:38:48 +0100, Paul wrote:
> Hi,
> 
> I did an update to the machine at work which included the broken version
> of init-tools (IIRC) which means that booting may not work (which it
> doesn't at work).
> 
> Is there any way to rescue said system? I know on the laptop I did it by
> using RIP Linux, chroot /mnt/linux and chkconfig the clamav stuff which
> seemed to be annoying the system.

First things first: You don't necessarily always need to go to the trouble
of finding/downloading/burning a rescue CD in order to rescue a system. In
the case of a misbehaving clamav, that is a network service, so it should
be coming up in runlevel 3. That means that if at bootup time you press 'a'
at the grub bootup screen and then add "single" to the kernel command line,
it will drop you into single-user mode (fedora core doesn't even ask for a
root password for this, last I tried it!) and you can rescue the system
from there. In single-user mode all non-network partitions should be
mounted just as in a normal system (unless of course there's a mount
problem).

> Problem is with the box at work is the crash occurs at the end of
> discovering and allocating PID values to network connectors and I've no
> idea what service controls that or how to switch it off so I can at
> least boot and manually fix the problems.

OK, you can look at the bootup processes as a tree. grub calls the kernel.
The kernel then starts the first process, which is called init. init looks
in the file /etc/inittab, which contains the top-level instructions on
how to boot up the system. (Usually inittab doesn't need to be mucked
with, unless you need to change the default runlevel, or (un)install some
very unusual software.) Then /etc/inittab refers to a file called
/etc/rc.sysinit, which does all the basic bootup tasks before starting the
services, and then calling /etc/rc.local, which is the last thing to be
run before login starts.

That really defines the parameters of your search.

So I would have a look through /etc/rc.sysinit for any mention of the
"allocating PID values to network connectors" message that you are seeing,
or whatever it is. Failing that, just search through all files in /etc for
the message - won't take long. Make sure you get the message exactly
right, no spelling mistakes! Here is a sample command to do the search:

grep -r 'allocating PID values' /etc

If not, that message might be outtputted by a binary command, so try
searching for the previous message, until you find something.

HTH,
-- 
Robin