How to you use arch livecd to rerun lilo?

plockery · 2005-07-24 05:48:15

I have arch and win95 dual-booted on older p2 350 pc.
Bootloader is lilo on MBR.
I use a windows image program to make images of partitions or even the whole disk.

However, in the past I have had trouble when recovering a partition image with lilo in the mbr - lilo gets messed up somehow and stalls.

My question is a simple one.

If this happens with arch, how do you use the livecd to rerun lilo to have lilo recover the boot process?

I have tried to boot from live cd into my existing arch install as the livecd says as follows:
boot: arch root=/dev/discs/disc0/part2 (partition2 is my arch partition)
but this does not seem to boot anydefferently from the first time install process.
I get to the same screen which asks me to type /arch/setup for first time install.
I don't know what to do next or even if where I am is correct.

Can someone give me the actual commands up to the point where I can just type in
#lilo
and have lilo rewrite the mbr?

Peter

Dusty · 2005-07-24 05:59:26

Boot into the live CD
mount /dev/hda2 /mnt/disk #use your device
cp /dev/hda /mnt/disk/dev
cp /dev/hda2 /mnt/disk/dev
cp /dev/hda1 /mnt/disk/dev #copy any devices that are referenced in lilo
chroot /mnt/disk
lilo

That *should* do the trick. Once the devices have been copied, they'll be there for good. I feel these devices should be available statically for situations like this, even though they are also managed by udev.

Dusty

plockery · 2005-07-24 07:18:23

Thanks dusty but no go.

I must not be booting into the livecd properly or something.

# mount /dev/hda2 /mnt/disk0

[I also tried # mount /dev/discs/disc0/part2 /mnt/disk0]

returns the error "mounting /dev/hda2 on /mnt/disk0 failed. no such file or directory".

I tired booting the live cd two ways:

1. # boot: arch OR

2. # boot: arch root=/dev/discs/disc0/part2

Either way makes no difference.

What am i doing wrong?

I thought the whole idea of the second option to boot the live cd would be that it should just bring up your normal hard drive setup.
Where is option 2 meant to take you?

Thanks for your help.

Peter

Mr Green · 2005-07-24 07:59:54

http://www.archlinux.org/docs/en/guide/ … .html#faq5

might help ,,,

post again here if you still need help ...

plockery · 2005-07-24 08:33:28

Thanks Mr Green!

Tha is just what I was looking for but did not realise it was in the installation guide.

I can rerun lilo the long way... through the mount and chroot instructions.

But for some reason, i cannot get arch to boot into my system.
All the partitions are intact since nothing has actually gone wrong yet... I wanted to get this straight before it did!

But the command at the boot point of the livecd "arch root=/de/vdiscs/disc0/part2" does nothing.

It just treats it like a new installation as if I had just typed "arch".

It seems like the livecd is just no recognising the root= parameter.

Do you know why this might be?

Peter

Mr Green · 2005-07-24 08:36:25

can you post your lilo.conf there may be a problem with it...

When you say arch will not boot do you get kernel panic?

Karma XXL · 2005-07-24 09:06:24

Have you created /mnt/disk0 before trying to mount?

About the root= parameter, if the LiveCD uses an initrd (which I don't know), it can easily override your root= parameter. I think this is what's happening here.

plockery · 2005-07-24 10:15:55

To Mr Green

1. Below is my lilo.conf - let me know if you see a problem.

#
# /etc/lilo.conf
#

boot=/dev/discs/disc0/disc
# This line often fixes L40 errors on bootup
# disk=/dev/discs/disc0/disc bios=0x80

default=arch
timeout=50
lba32
prompt

image=/boot/vmlinuz26
label=arch
root=/dev/discs/disc0/part2
read-only

other=/dev/discs/disc0/part1
label=Windows_95

# End of file

2. What I mean by "arch does nothing" is that it simply boots to the new installation screen and completely ignores the root= parameter.
If I continue it goes through the new install setup.
Nothing wrong with the boot process as such, except that I can't boot into my arch install from the livecd like you are supposed to be able to.

To Karma XXL

Yes the livecd does use a initrd.img.
But surely this would have been come up as a a problem many times before for anyone trying to boot into their arch install for any rescue purpose.

Is there a way around it?

Should this behaviour then be posted as a bug?
If so how do I do that?

Peter

Karma XXL · 2005-07-24 13:26:51

I think it's not a bug, rather a lack of feature. I don't think the install CD was meant for this type of rescuing, so you should post a Feature Request in the Flyspray.

Note: this is my opinion. If someone knows how this is possible, please elaborate.

Mr Green · 2005-07-24 13:37:25

emmm it happens sometimes mbr gets messed up, more likely windows overwriting it ...

Using the above method you can recover mbr & re run lilo ....

Any live cd will be able to get you up & running again may I suggest Archie ;-)

plockery · 2005-07-24 13:41:01

Sorry, karma xxl, but that doesn't make much sense to me.

If the live cd is not meant to boot into your current arch install, then why in the world is the instruction there that tells you how you are supposed to be able to do so in the first place!!!!

Not only that, the link that Mr Green gave to the installation guide has it there as well and at least the long version of those instructions does work.

IMHO if I find an instruction on something as basic as the livecd from which I take it most people install and that instruction can't be done, then that is a bug - let alone being extremely misleading to the newcomer.

If i can find out where to register that this may be a fault I will try and do so.

But thanks for your interest and help anyway. I appreciate it.

Peter

plockery · 2005-07-24 14:12:46

OK, I have partially solved the problem.

Looked at the bug reports and found out that this bug has already been posted - #2623.

Apparently, the line to boot into an existing system should be

# boot: arch root=/dev/discs/disk0/part2 noinitrd ro

Your hunch karma xxl that the livecd initrd was overriding things appears to have been correct.

My only problem now is that when I add the "noinitrd ro" addition there is a serious loss of functionality, especially if your system is set to startx as mine is into windowmaker.

It boots into windowmaker alright but both mouse and keyboard appear to be stalled. So I cant do anything anyway.

Not much of a solution for a rescue option!!!

So I suppose I am still stuck with the long option of mounting the partition and /dev manually and chroot into the mount.

Peter

Arch Linux

#1 2005-07-24 05:48:15

How to you use arch livecd to rerun lilo?

#2 2005-07-24 05:59:26

Re: How to you use arch livecd to rerun lilo?

#3 2005-07-24 07:18:23

Re: How to you use arch livecd to rerun lilo?

#4 2005-07-24 07:59:54

Re: How to you use arch livecd to rerun lilo?

#5 2005-07-24 08:33:28

Re: How to you use arch livecd to rerun lilo?

#6 2005-07-24 08:36:25

Re: How to you use arch livecd to rerun lilo?

#7 2005-07-24 09:06:24

Re: How to you use arch livecd to rerun lilo?

#8 2005-07-24 10:15:55

Re: How to you use arch livecd to rerun lilo?

#9 2005-07-24 13:26:51

Re: How to you use arch livecd to rerun lilo?

#10 2005-07-24 13:37:25

Re: How to you use arch livecd to rerun lilo?

#11 2005-07-24 13:41:01

Re: How to you use arch livecd to rerun lilo?

#12 2005-07-24 14:12:46

Re: How to you use arch livecd to rerun lilo?

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