Unable to boot from CD

[Sauparna]

Previously I had a working Plan9 (3rd. Ed.) installation on my desktop, which had Pentium 4 processor. I am unable to boot from the same Plan9 CD, and even the 4th. Ed. CD, on my laptop. I get this error message:

PBS1...
Plan9 from Bell Labs
ELCR: 0C98
pcirouting: South bridge 8086, 2919 not found.
plan9.ini probe ... probing floppy ... probing bios ... probing CD ... probing sd ... no plan9.ini
cpu0: 2189MHz Core 2/Xeon
bios (usb) loading disabled
Boot devices: fd0
boot from:_

It stays put at this prompt with the blinking cursor. What could be the problem?

BTW, this page (http://plan9.bell-labs.com/wiki/plan9/Mailing_lists/index.html) suggests not posting to this group directly, but the 9fans link (http://mail.9fans.net/listinfo/9fans) doesn't work so I wrote here. The page is outdated, maybe?

[erik quanstrom]

From the above, the problem is not an installation that worked before,
and does not anymore, since this is not a Pentium IV anymore but a
Core 2/Xeon.
Since it loads the floppy image, El Torito is supported. Now, this is
the exploration of the mass storage that seems to pose problems.
Do your disks have MBR, or GPT or something else (RAID)?
Are you able to enter a specification for boot from?

the floppy loading and emulation is a bios trick. nothing to do with
the boot image itself.

the problem is that plan 9 is not detecting the cd drive. this could
be for two reasons
- the controller is just not supported. if it's not usb, i'd be surprised
if it didn't emulate ide or ahci.
- unless things have changed recently, the distribution cd won't boot
unless your cdrom is on D:. this precludes any ahci and quite a bit of
ide-emulating devices.

the 9atom cd doesn't have the second problem. it doesn't care where
the cd is configured.

hth.

- erik

[t***@polynum.com]

Post by Sauparna
[...]
cpu0: 2189MHz Core 2/Xeon
bios (usb) loading disabled
Boot devices: fd0
boot from:_

From the above, the problem is not an installation that worked before,
and does not anymore, since this is not a Pentium IV anymore but a
Core 2/Xeon.

Since it loads the floppy image, El Torito is supported. Now, this is
the exploration of the mass storage that seems to pose problems.

Do your disks have MBR, or GPT or something else (RAID)?

Are you able to enter a specification for boot from?

[c***@gmx.de]

9load doesnt detect your storage devices. you could try plan9front cd
(http://r-36.net/9front/) wich uses a different bootloader wich uses
bios to access storage devices (so it doesnt need a custom driver)
wich will probably gets a kernel loaded.

if the kernel also doesnt detect the ide/sata controller, type !rc at
the bootargs prompt to get into a pre boot shell, then run:

grep -n '^01' '#$/pci/'*ctl

often, its just a matter of adding pci vid/did to the ide/sata driver
to get it running.

--
cinap

[Sauparna]

I tried several things and help, again, is appreciated.

@erik, @cinap:
9front and 9atom booted properly. 9atom live-boot option didn't work,
but installation proceeded to [mountdist]. At that point I couldn't
figure out a way to point it correctly to the distribution, my linux
partition, though suggested, wouldn't mount. I had a plan9.iso there.
Before that at [partdisk] I manually specified a 3GB partition in some
raw free space I had. So I aborted, and then on I cannot boot into
Linux (I had backed up, so no worries). Why should the existing linux
boot partition get spoiled? Booting in with a rescue CD (Ubuntu Rescue
Remix), I can 'fdisk -l' all the partitions as they were. The NTFS
partition (I have Windows installed), and other ext3 partitions can be
mounted and navigated except for the boot partition (where root was
mounted).

@Thiery, I could key in characters at the 'boot from' prompt, but
didn't try anything then. I have a MBR, not GPT. It's a typical dual-
boot layout, having installed Ubuntu second, after Windows.

[c***@gmx.de]

theres a bug in plan9 fdisk causing partitions to get forcefully
rounded to cylinder boundries. causing existing partitions
to "move" even if they where never modified due to wrong
disk geometry detection or just non-cylinder-aligned
partitioning.

this was fixed in 9front long ago.

--
cinap

[Sauparna]

I tried several things, and help, again, will be appreciated. With the little knowledge I have I will try to explain the procedures.

@Thierry: I have a MBR, and not GPT. I have Windows and Linux (Ubuntu) and dual-boot through GRUB; as is the standard setup found when Ubuntu is installed second and GRUB writes the MBR. Secondly, I didn't know what to specify at the 'boot from:' prompt, and I haven't tried it yet. Yes, I can key in text at the prompt.

@cinap: 9front boots, and dies. I don't get installation / boot options at all. No prompt either.

@erik: 9atom worked. Booting from CD (option 2) didn't, but installation (option 1) proceeded fine till I got stuck at [mountdist], couldn't locate the distribution and it wouldn't proceed till I specify a correct source, so I quit at that point, rebooted and ended up losing my grub. I was careful enough to specify the right partition for installation, however I didn't choose the suggested layout but modified it (specifying start and end blocks) to occupy only 3GB of the raw free space I had. Booting from a live Ubuntu CD I can now list existing partitions using fdisk -l, but I am unable to mount my Ubuntu boot partition. 'mount' doesn't recognise the file system. The NTFS and another ext2 partition that I had can be mounted properly.

Here're my partitions. I have lost /dev/sda5 which was my boot partition. (Backed up, so no worries).

Device Boot Start End Blocks Id System
/dev/sda1 * 1 6374 51199123+ 7 HPFS/NTFS
/dev/sda2 6375 31298 200202030 f W95 Ext'd (LBA)
/dev/sda3 31299 37359 48684982+ 83 Linux
/dev/sda4 37360 37759 3213000 39 Plan 9
/dev/sda5 6375 30689 195310206 83 Linux
/dev/sda6 30690 31297 4883728+ 82 Linux swap / Solaris

So,

1. Why should my MBR get overwritten when I aborted the Plan 9 installation at [mountdist]? And why did my boot partition get spoilt?
2. What should I do to get the [mountdist] step to completion?

[Sauparna]

I tried several things, and help, again, is appreciated.

@Thiery: I could key in characters at the 'boot from' prompt, put didn't try anything then. I have an MBR and not GPT, it's a dual-booted system with Ubuntu having been installed second, after Windows. I used to boot through GRUB, as is the standard setup.

@eirk: 9atom worked. The live-boot option didn't but the installation proceeded till [mountdist] where I was unable to point the installer to the distribution archive. I aborted and rebooted at this point, and ended up losing GRUB and the Linux boot partition (I have backed up, so no worries).

@cinap: 9front booted properly.

So, I am wondering why 9atom would write to the MBR then, isn't that option asked for after [mountdist]? I was careful enough to specify the correct partition at [partdisk]. There was a default layout suggested, which I manually modified to take up 3GB only. Other than that, I made no changes. Booting into my system with a live rescue disk (Ubuntu Rescue Remix), I can 'fdisk -l' the partition table, everything shows up, but I can't mount the ubuntu boot partition. Other NTFS and ext3 partitions are fine, can be mounted and navigated.

Secondly, what do I do at [mountdist] to correctly specify a dist archive?

[erik quanstrom]

Post by Sauparna
9front and 9atom booted properly. 9atom live-boot option didn't work,
but installation proceeded to [mountdist]. At that point I couldn't
figure out a way to point it correctly to the distribution, my linux
partition, though suggested, wouldn't mount. I had a plan9.iso there.
Before that at [partdisk] I manually specified a 3GB partition in some
raw free space I had. So I aborted, and then on I cannot boot into
Linux (I had backed up, so no worries). Why should the existing linux
boot partition get spoiled? Booting in with a rescue CD (Ubuntu Rescue
Remix), I can 'fdisk -l' all the partitions as they were. The NTFS
partition (I have Windows installed), and other ext3 partitions can be
mounted and navigated except for the boot partition (where root was
mounted).

the fact that the live-boot doesn't work is sort of well-known.
sorry about that.

i don't know why your mbr is getting wacked. that's antisocial.
i never dual-boot myself.
i'll try to look at it this weekend. it's probablly as thiery points out
that we're trying to overlay some chs crap onto a massive sata drive.

can you send me the output of cat /dev/sd*/ctl when you get a chance?
also, could you send me a fdisk summary of what the partition table
looks like? a raw dump of the first 16 sectors of the drive would be
even better.

- erik

[Sauparna]

Post by erik quanstrom
i don't know why your mbr is getting wacked. that's antisocial.

erik, just a point here. I think I mislead you. My partition got spoiled,
the mbr was fine, for I got a grub prompt (in stead of the the usual grub
screen). It must have been that grub couldn't boot the right thing.

(I'll post the outputs soon.)

-Sauparna

[Sauparna]

Here's 'fdisk -l'. (sdb is a usb disk I connected later.) The warnings
seems to corroborate cinap's comment, is it so?

The dump: http://dl.dropbox.com/u/10125317/sda.16.dump
(dd if=/dev/sda of=sda.16.dump bs=4096 count=16)

That should be the 1st. 16 sectors I hope. I checked (dumpe2fs) the bs of
sda3 (this partition is intact) to use the above bs. Also, to boot into my
Windows, I had fixed the mbr using the Windows 'fixmbr' command. So you
will find an intact mbr, and therefore not a very useful thing, the dump
will turn out to be.

This exercise is turning out to be interesting. May I ask how you would
have worked on the dump, and what could be learnt from looking into it?

And what did you mean by : cat /dev/sd*/ctl, it didn't work for me? I used
sda and sda5.

---------------------------------------------------------------------------------------------------
Warning: Partition 5 does not end on cylinder boundary.
Warning: Partition 6 does not end on cylinder boundary.
Warning: Unable to open /dev/sr0 read-write (Read-only file system).
/dev/sr0 has been opened read-only.
Error: /dev/sr0: unrecognised disk label

Disk /dev/sda: 320 GB, 320070320640 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 6374 51199123 7 HPFS/NTFS
/dev/sda2 6375 31298 200193997 f Extended LBA
/dev/sda5 6375 30689 195302205 83 Linux
/dev/sda6 30690 31297 4875727 82 Linux swap
/dev/sda3 31299 37359 48676950 83 Linux
/dev/sda4 37360 37759 3204967 39 Plan 9

Disk /dev/sdb: 1000 GB, 1000202273280 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdb1 * 1 97 779121 b FAT32
/dev/sdb2 98 1403 10482412 83 Linux
/dev/sdb3 1404 121601 965482402 83 Linux
---------------------------------------------------------------------------------------------------

[Sauparna]

(I am slightly embarrassed to have made three conflicting posts in
succession. The Google-group interface was, for some reason, not sending my
posts through. So I kept trying over 12 hours, and every time I rewrote my
post. Anyway, that's not important any more.)

Before I end I must mention that the problem with the 9atom installation
still remains. I re-installed Linux and then Plan9. The partitions moved
again, rendering them unusable. I restored linux again, and now boot into
the 9atom installation from grub. Works, but very slow to boot.

Two small corrections. Previously, I was getting stuck at [mountdist]
because of read errors on the installation cd, and, 9front worked fine.

Thanks for your help. I would like to close the thread here.