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I'm trying to upgrade a rh 9 system to centos 4.1.

I burned the part 1 iso image onto a cd using cdrecord.

Given my experience upgrading rh installations, I next tried booting
from the cd. It fails with the message(s):

ISOLINUX 2.11 2004-08-16 Copyright(C) 1994-2004 H. Peter Anvin
isolinux: Disk error 80, AX=42CC, drive 9F

Boot failed: press any key to retry.

I have tried booting the cd on a couple of systems and it does the
same. Moreover, I know that bootable cd's work on the system (laptop)
in question, as that's how I put rh 9 on the system in the first
place.

However, I've looked at the cd (under windows) and there are
directories on the cd, not just an iso file. So, I don't think I
wrote the cd wrong.

Am I correct in assuming that perhaps there was a write error on the
cd and the boot image was corrupted?

Is it likely that the cd contains a useful copy of the installation if
I can just get it booted? (Or is the cd just a coaster and should I
write another one?)

Is it possible to boot the cd from the linux boot I already have
installed? The target system is a laptop and I have a choice of a
floppy or a cd, but not both at the same time.

Thanks in advance,
-Chris

Chris F Clark wrote:

> I'm trying to upgrade a rh 9 system to centos 4.1.

Good for you, but it would be much better to save everything and do a
clean install. Going from a 2.4 kernel to a 2.6 kernel using the update
meathod is not a good idea. Major changes from RHL9 to CentOS4.1 also
apply, lots of things have changed.

> I burned the part 1 iso image onto a cd using cdrecord.

How???? You did not show the cdrecord command you used....

> However, I've looked at the cd (under windows) and there are
> directories on the cd, not just an iso file. So, I don't think I
> wrote the cd wrong.

You may have, it might have been your cdrecord command or a problem with
the media or burner or ????? Whatever the reason you have a bad CD.


> Is it likely that the cd contains a useful copy of the installation if
> I can just get it booted? (Or is the cd just a coaster and should I
> write another one?)

Yes, it is a good idea to write another one. As a suggestion write the
new CD at the slowest speed possible, yes I know this takes a long time
but the quality will improve.


--
Contained within the Microsoft EULA;
This Limited Warranty is void if failure of the Product has resulted
from accident, abuse, misapplication, abnormal use or a virus.

Let me repeat this one question I asked before:

> Is it possible to boot the cd from the linux boot I already have
> installed? The target system is a laptop and I have a choice of a
> floppy or a cd, but not both at the same time.

Actually, what I'm really curious about is that I have the .iso files
on the hard disk of the system in question. Is there a way to
use/convert those .iso files into something that I could use (without
writing them to a cd) to upgrade the system? I have very little
interest in having a cd to do the upgrade. It's a waste of a cd to
me. While that's not a big waste, it is a finite non-renewable
resource. When I've used up my cd's, I have to go to Staples to buy
more or order ones from a website and wait, etc.

I recall reading something previously that suggested that one could
put the images (on a server or on a disk) and upgrade from there.
However, I can't find the pointer to that information now and could
use some help in getting pointed the right way.

(Alternately, if there is something different I should download onto
the disk to upgrade directly from the disk, I can do that to.)

Thanks,
-Chris

On Sun, 02 Oct 2005 20:03:08 +0200, Chris F Clark <cfc@shell01.TheWorld.com> wrote:

> I'm trying to upgrade a rh 9 system to centos 4.1.
>
> I burned the part 1 iso image onto a cd using cdrecord.
>
> Given my experience upgrading rh installations, I next tried booting
> from the cd. It fails with the message(s):
>
> ISOLINUX 2.11 2004-08-16 Copyright(C) 1994-2004 H. Peter Anvin
> isolinux: Disk error 80, AX=42CC, drive 9F
>
> Boot failed: press any key to retry.
>
> I have tried booting the cd on a couple of systems and it does the
> same. Moreover, I know that bootable cd's work on the system (laptop)
> in question, as that's how I put rh 9 on the system in the first
> place.
>
> However, I've looked at the cd (under windows) and there are
> directories on the cd, not just an iso file. So, I don't think I
> wrote the cd wrong.
>
> Am I correct in assuming that perhaps there was a write error on the
> cd and the boot image was corrupted?

Did you bur the CD yourself? Do you have the iso image on disk somewhere?

From the linux you already have,

n=$(( (the size of iso in bytes)/2048 - 50 ))

dd if=/dev/cdrom bs=2048 count=$n | cmp isoimage -

If you get "EOF on stdin" the CD is likely OK.
Notice that it does not work to compare the last part of the
iso this way because of a bug in the linux kernel. This bug
does not affect the operation of the cd as a mounted file system.

If you want to burn cd's that are possible to verify with dd,
you need to pad the iso image on the cd when you burn it.

My guess is that the CD is corrupted.

-Enrique

On Tue, 04 Oct 2005 18:03:37 +0200, Chris F Clark <cfc@shell01.TheWorld.com> wrote:

> Let me repeat this one question I asked before:
>
>> Is it possible to boot the cd from the linux boot I already have
>> installed? The target system is a laptop and I have a choice of a
>> floppy or a cd, but not both at the same time.
>
> Actually, what I'm really curious about is that I have the .iso files
> on the hard disk of the system in question. Is there a way to
> use/convert those .iso files into something that I could use (without

I can only provide a tiny bit of information that may or may not become
part of a solution if other bits are found.

Consider the stack of software layers in ordinary disk accesses,
the hardware disk access routines, the block device abstraction,
the file system on top of that, and finally files accessed with
open, read, write and close. Now there is a mechanism to take
an ordinary disk file and make it look like a new block device,
which builds upon ordinary file read and write instead of hardware
access. This is called "loop device". When running an ordinary
Linux session, you can mount an iso image through a loop device
and peruse the contents of the iso much as you would a CD.

Now, what happens during an install from a CD?

Allow me to fill in gaps in my knowledge with some guessing, and
take the following with the corresponding grains of salt.
Also consider that my memory tends to mix things up more than
usual, so everything must be checked before one can rely on it.

I have seen someplace that bootable CD's have two parts, one
resembles a bootable floppy, and one part is a traditional
CD file system. The bootable floppy contains essentially kindof
a boot loader, which is capable of reading, from either the
first or the second part, and load into memory a) a linux
kernel, and b) a ramdisk image that the linux kernel will use
as its initial root file system. Then the installation program
is inside this ramdisk. The image file of the ramdisk may
be called initrd. It may be compressed.

I presume that with some (much?) fiddling, it should be possible
to run the installation program off a live disk-based file system.

The installation process partitions the disk(s), creates
file systems in the partitions (but skips this if you are
upgrading) and mounts the paritions under some directory
near the ramdisk root. My experience is with Redhat/Fedora,
and a mountpoint name of /sysimage comes to mind.

Armed with this information, perhaps you can explore the contents
of the iso image, and decide on a strategy from there.

In the end, the installation process consists in creating a
basic directory structure, and then running the package
manager to install a long list of packages. The package
manager must accept options to install under an alternate root,
not into the ram fs. If you only have the list of packages,
quite likely you will get a usable result by just installing the
packages while running on a live system.

On the other hand, assembling that list of packages can be
a nightmare because of large groups of packages that are
circularly dependent and must all be installed in one go.

Most likely there is no need to run a special kernel during
installation. The currently running kernel should do fine.

Oh, I forget that the installation CD also has things to
set up the keyboard and screen under the most varied and
adverse conditions. But that is perhaps not the essential
challenge when you shall install on just one or two
specific and known computers.

And yes, to mount an iso image under /mountpoint,

mount -t iso9660 -o ro,loop /path/to/image.iso /mountpoint

If you need to install to partitions that are already the live
root fs, you may need to bind-mount those partitions under your
/sysimage. Man mount, search for --bind. Essentially

mount --bind olddir newdir

After that, the files in olddir are available in two places.


-Enrique

Chris F Clark wrote:
> I'm trying to upgrade a rh 9 system to centos 4.1.
>
> I burned the part 1 iso image onto a cd using cdrecord.
>
> Given my experience upgrading rh installations, I next tried booting
> from the cd. It fails with the message(s):
>
> ISOLINUX 2.11 2004-08-16 Copyright(C) 1994-2004 H. Peter Anvin
> isolinux: Disk error 80, AX=42CC, drive 9F
>
> Boot failed: press any key to retry.
>
> I have tried booting the cd on a couple of systems and it does the
> same. Moreover, I know that bootable cd's work on the system (laptop)
> in question, as that's how I put rh 9 on the system in the first
> place.
>
> However, I've looked at the cd (under windows) and there are
> directories on the cd, not just an iso file. So, I don't think I
> wrote the cd wrong.
>
> Am I correct in assuming that perhaps there was a write error on the
> cd and the boot image was corrupted?
>
> Is it likely that the cd contains a useful copy of the installation if
> I can just get it booted? (Or is the cd just a coaster and should I
> write another one?)
>
> Is it possible to boot the cd from the linux boot I already have
> installed? The target system is a laptop and I have a choice of a
> floppy or a cd, but not both at the same time.
>

IIRC, isolinux is using its own ATAPI CD driver. If your CD is not
compatible with it, you'll get the results you describe. I can get
the same results with a SCSI -connected CD.

The El Torito disk image seems to be correctly burned, else you'd
not get the isolinux banner.

The El Torito CD booting works by replacing the primary floppy
drive in BIOS temporarily with a disk image on the CD. Isolinux
uses that to get into the processor, but it does not use the
simulated disk for reading the kernel proper.

You should first get the details of the CD drive, and then look
for a boot CD compatible with it.

Another possibility is to use another Linux computer as a server
and use a network boot, if the BIOS supports it.

HTH

--

Tauno Voipio
tauno voipio (at) iki fi