[lug] [lilo.solution]

JEFF PFOHL pfohl at sandia.gov
Tue Mar 28 22:56:47 MST 2000


I've emailed/posted about this problem and it is finally solved (well
almost). But I finally, with everyone's help, figured out the problem
AND learned some neat things along the way. Here's a rather long
write-up as to how the problem was solved for everyone's
benefit. Special thanks to everyone who offered advice and special
thanks to Murphy Leo O'Dea who really broke this problem open for me
and provided invaluable advice. And to Norm Modine for advice on using
cat and answering questions throughout this process. This story
necessarily leaves out all the dead ends I ran into which led no where
but to frustration.

The original problem (briefly), I was trying to install Red Hat 6.1 on
my IDE HP Vectra. This machine currently runs RH5.2 with no
problems. The 6.1 install, on a new disk, went smoothly but the reboot
stuck on "LI".

Lots of things were examined/tried over the last several days. Finally
Murphy asked me about my ribbon cable set-up and what was
master/slave. 

I'll quote Murph "I believe it's trying to write a new boot record to
your Tape Device!" Indeed he was correct. The wiring WAS (and no I
don't know how it ever worked with 5.2):

CD-Rom was:
 /dev/hdc   IDE2   Secondary Master        End of second ribbon cable

Harddrive was:
/dev/hdd   IDE3   Secondary Slave          Middle of second ribbon
cable

Tape drive was:
/dev/hda   IDE0   Primary Master             End of first ribbon cable




So I rewired like Murphy suggested:

CD-Rom is now:
 /dev/hdc   IDE2   Secondary Master        End of second ribbon cable

Harddrive is now:
/dev/hda   IDE0   Primary Master             End of first ribbon cable

Tape drive is not plugged in (see below).

Despite Murphy's good advice on how to manually mount things I decided
to do a clean install for RH6.1. Easy and less painful IMHO.

The RH 6.1 install went SMOOTHLY. Booted just fine.


OK now it is time for me to learn some very neat things. And I get to
use Murphy's/Norm's advice on manually mounting plus some other
"tricks". With my tape device disabled and my RH5.2 still having all
my files on it I need to access this drive. For the short term to keep
my computer up so I can get email and in the longer term to get the
files from my RH5.2 to my RH6.1 disk.

OK with the new cabling put in the old RH5.2 disk and boot. OOPS
doesn't work:

"loading advansys module
scsi : 0 hosts
/lib/advansys.o : init_module: Device or resource busy
hdc: tray open or drive not ready
     attempt to access beyond end of device
hdc: tray open or drive not ready
     attempt to access beyond end of device
hdc: tray open or drive not ready
     attempt to access beyond end of device
16:0d rw=0, want=2, limit=0

EXT2-FS: unable to read superblock
hdc: tray open or drive not ready
attempt to access beyond end of device
16:0d rw=0, want=2, limit=0
FAT bread failed
kernel panic: VFS: Unable to mount root fs on 16:0d"

OK this isn't suprising. It wants to boot /dev/hdC and the device is
now wired as /dev/hdA. This is also perhaps more detail than you
wanted but I saw this a lot today so thought I'd put it out there. It
also relates to a problem at the end which is important and in need of
further advice.

OK try a "trick" of sorts:

Reboot the machine with a custom boot floppy. Get to the "boot:"
prompt and try

boot: linux single root=/dev/hda13 initrd=

What this SHOULD do is start the boot in single-user mode with the
root partition set to my new root partition (hda13 rather than hdc13
as before). The empty initrd specification bypasses the
installation-related image on the boot diskette which causes you to
enter single user mode immediately.

I logged in as root. I was going to simply edit /etc/lilo.conf to
reflect /dev/hdaXX instead of /dev/hdcXX. BUT the file system is
READ-ONLY. FRUSTRATING. WHY is it "read only"???

OK make a rescue floppy from the RH5.2 CD and try rescue mode. Boot
off custom boot diskette and at the "boot:" prompt type

boot: rescue

Now insert the floppy with rescue.img.

Great I'm now logged in as root. Following Norm's/Murphy's advice
(although he expected me to use it for my 6.1 install I actually was
saving my 5.2 this time around):

Boot with a rescue diskette; manually mount /dev/hda13 by creating a
directory /junk, then "mount -t ext2 /dev/hda13 /junk ".  Edit
/junk/etc/lilo.conf.  Then run lilo from /junk/etc using the -r
switch.

HOWEVER there isn't an editor present. No vi, no emacs, no ed,
nothing. 

OK first things first let's explicitly cover what I did right as I
logged in:

root> mkdir /junk
root> mount -t ext2 /dev/hda13	/junk
root> mount -t ext2 /dev/hda1	/junk/boot

root> cd /junk/etc
root> cat lilo.conf

OK I now know exactly what lilo.conf looks like. I need to change all
hdc to hda but with no editor. Try the "cat" command. Thanks Norm for
this hint. Write it out to a separate file in case this doesn't work.

root> cat >jeff.lilo.conf

Type it in line by line, use [ctrl] d to exit and save.

WORKS!!

root> cp /junk/etc/jeff.conf /junk/etc/lilo.conf
root> /junk/sbin/lilo -r /junk

Added linux *

WORKS!!

Do the same for fstab to correct all hdc to hda

root> cat /junk/etc/fstab
root> cat >jeff.fstab
root> cp /junk/etc/jeff.fstab /junk/etc/fstab
root> cd /
root> umount /junk/boot
root> umount /junk

Shut it down. Reboot. WORKS!!!

But there is an error on boot up and my tape drive is still not hooked
up.

Reboot:

{snip}

Mounting local file systems
EXT2-FS: Unrecognized mount option defaults

mount: wrong fs type, bad option, bad superblock on /dev/hda1 or too
many mounted file systems.

WHAT?? Here is my /etc/fstab in case it is relevant:

/dev/hda13              /                       ext2    defaults        1 1
/dev/hda1               /boot                   ext2    detaults        1 2
/dev/hda5               /home                   ext2    defaults        1 2
/dev/hda9               /opt                    ext2    defaults        1 2
/dev/hda11              /tmp                    ext2    defaults        1 2
/dev/hda6               /usr                    ext2    defaults        1 2
/dev/hda7               /usr/local              ext2    defaults        1 2
/dev/hda10              /usr/src                ext2    defaults        1 2
/dev/hda8               /var                    ext2    defaults        1 2
/dev/hda12              swap                    swap    defaults        0 0
/dev/fd0                /mnt/floppy             auto    noauto          0 0
/dev/cdrom              /mnt/cdrom              iso9660 noauto,owner,ro 0 0
none                    /proc                   proc    defaults        0 0

And my /etc/lilo.conf:

boot=/dev/hda
map=/boot/map
install=/boot/boot.b
prompt
timeout=50
image=/boot/vmlinuz-2.0.36-0.7
        label=linux
        root=/dev/hda13
        initrd=/boot/initrd-2.0.36-0.7.img
        read-only


Lessons learned:

1. check the ribbon cables. Helps if you understand what they mean,
   thanks Murphy.

2. the rescue.img is your friend, make this floppy when you
   install. EVEN If the install was easy, you never know when it may
   be useful.

3. cat is very versatile and takes the place of an editor in a
   pinch. It can be tedious but alas saved me.

4. the Linux community is always willing to help

Questions still unanswered:

1. how can I get my Seagate Travan tape device hooked back up?? The
   only cable available is /dev/hdb, IDE1, Primary Slave, Middle of first
   ribbon since the 2nd ribbon slave won't reach. I can fix this. I
   need to hook it up on my RH5.2 and RH6.1 drives.

2. why was the disk "read only" when I did a

boot: linux single root=/dev/hda13 initrd=

3. where were the editors from the rescue.img reboot?


It seems fairly straight forward reading this message but in the midst
of this I was truly lost. Editors not working, operating systems not
being found, read-only file systems, editing /etc/lilo.conf various
times with the "linear" option and without it, altering the ribbon
cable hookups, rerunning lilo, checking for a geometry mismatch of
some sort, learning to use cat in place of an editor, etc.

Thanks to everyone who offered suggestions and support. And if you
have any clues on the above 3 remaining questions please let me know.



-- 
				JEFF PFOHL
			 	E-MAIL: pfohl at sandia.gov
				PHONE : (505) 844-7033  work
					(505) 299-9516  home
        				(505) 844-6729  fax
				http://nucalf.physics.fsu.edu/pfohl

"My grandfather once told me that there are two kinds of people: 
 Those who do the work and those who take the credit. He told me to 
 try to be in the first group; there was much less competition."

 - Indira Ghandi, the late Prime Minister of India








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