CD drive not found (GRUB problem?)
 

Hi :)
So I've installed Ubuntu 8.04 some weeks ago, and I've found out that my CD-drive isn't working.

Please see this thread for further information:
http://ubuntuforums.org/showthread.php?p=4924332

1) I do not use ubuntu but me thinks we have a similar kernel to scsi emulation and devices.

I have read your other thread....but could not see if you had looked at a certain /dev/ entry so forgive me if you already have

firstly I have ide controller jumper master dvd burner and one sata hard drive

bios is made to think sata is non-raided and made ata device but bios still does not put it in the ide search results.

b) grub can be tricked by bios boot order but if it does not recognise a device its skips it and numbers the next detected device as hd (x + 1)

so in your link....I translate that as

1 skipped
2 skipped
3 ide = (hd0)
balance skipped

However if you have made a bootable grub cd.....the cd is detected but not detected if you are booting a hd.

2) so when your hard drive is booted....check for /dev/sr0

however Mdv gives good symlinks and I have

/dev/cdrom1 with group cdwriter
/dev/dvd1 ditto
/dev/sr0 ditto

That's what I think too :)
but what do you mean with 'balance skipped'?

I'll try that with a super grub disk, but how can that help me?

Sorry, but is Mdv = Mandriva?

not found

So how do I make grub recognize my devices? And (probably stupid question: ) can't I just manually add the entries to the device.map file?

TIA

If I'm wrong someone please correct me.

But what does Grub have to do with your cd-rom? Grub is a boot loader, all devices are checked at POST, after the POST your bios turns over control to the MBR all Grub does is look for the kernel then turns over control to the kernel. I have seen no grub entry that has anything to do with the cd-rom on any system I've built.

I would first check and make sure your bios is detecting the cd-rom also look for a bad cable. You may also want to turn off plug N Play in the bios this can sometime cause problems. Another problem I have seen is if your system is a proprietory system and it doesn't use the standard Atapi interface. It could also be that the cd-rom is going bad.

I had a system I installed Debian on that would boot to the cd-rom get part way through the install, when it checked for the cd-rom (that it just booted to) it couldn't find it. It ended up being a bad cd-rom, I replaced the drive and had no problems.

check dmesg and see if it lists the drive.

I wouldn't rule out the kernel having a bad setting either, but as for the problem being with Grub I doubt it.

I'm fairly certain that it is grub as I have ironed out any other possibilities. Let me explain:

1)
When I installed Ubuntu I also installed grub to the MBR. As I also have a Windows Vista installation, the Windows bootloader was now chainloaded from grub. (Which in turn means that the Windows bootloader now got the device information from grub and not directly from the bios, afaik).
The cd-rom drive didn't work in Ubuntu nor Vista, BUT I could boot from a live cd. (which rules out the possibility of my drive being broken)

2)
I then tried chainloading grub from the windows bootloader (the windows bootloader was now in the MBR and grub was at the start of my linux partition), and now my drive also worked in Vista but still not in Ubuntu.

So I doubt that it doesn't have something to do with grub. :) (about my system being proprietary, I have no idea. I can post my specs if you want)

'dmesg | grep cdrom' doesn't output anything.

All of your drives are checked in the POST. Grub has nothing to do with devices. After the POST, it goes directly to the mbr and looks for the kernel and boots (if there is a valid entry) and obviously drivers When you had Grub installed and booted vista it wasn't getting device information from Grub, but from BIOS.

So now your chainloading Ubuntu from vista and can boot into both? And it is your CDRom that you can't use in Ubuntu? Your last post was a little confusing, you referred to 'drive' not specifying whether it was the CD or hardrive.


If you want to resolve your problem you will need to look somewhere other than your bootloader.
Here's a link about Grub specifically for Ubuntu:
http://users.bigpond.net.au/hermanzone/p15.htm#

Take a look at this link it gives detailed info on what happens booting a linux system.

The problems you are having are either from a bad cd-rom or cable or from the bios prior to writing to RAMdisk or maybe in your kernel.<== don't think so.

What kind of cd-rom are you using IDE or SATA? Is it in Dell system? Please post your system specs.

I don't understand how this problem can be from a faulty drive. How can it be that it works in Vista and that I can boot from a cd then?
About the bios, I think that the bios doesn't communicate properly with grub.

I have a Zepto Znote 6625WD laptop. My cd-drive is a Samsung DVD-RW slot-in drive.
About IDE or SATA, my bios sees it as:
IDE Channel 1 Master: 160 GB SATA1
IDE Primary/Slave: CD-ROM
which I assume means that my cd-drive is IDE?
I also have the output of 'lshw' and the output of CPU-Z (a windows program, that I run (runned?) from within vista).
CPU-Z output
lshw output

I understand your frustration, but you have to understand something is not seeing the drive as it should. Grub has nothing to do with this, after the POST I/O information for booting is written to RAMdisk. When control is passed to the MBR Grubs first stage looks for the second stage. The only information Grub needs from the bios is the device holding Grubs second stage. When control is passed from the bootloader to the Kernel the kernel will take the information from Ramdisk to set up the right drivers for listed devices by the bios.

It could be that this notebook is using a dvd-rom not recognized by the kernel.
Have you checked your bios to see if plug N play is disabled? If not disable it and see if that helps.

There's nowhere in my bios where it mentions Plug N' Play, however there's these options (if they're of any help):
(Name, present value and other values (in brackets))
Large Disk Acces Mode: DOS (Other)
Local Bus IDE adapter: Both (Disabled, Primary, Secondary)

CPU feature:
- No Execution Mode Mem Protection: Enabled (Disabled)
- Intel (R) Virtualization Technology: Enabled (Disabled)
FACP-RTC S4 Flag Value: Enabled (Disabled)

PXE OPROM: Enabled (Disabled)

Legacy USB Support: Enabled (Disabled)
Boot-time Diagnosis Screen: Disabled (Enabled)
QuickBoot Mode: Enabled (Disabled)
AHCI Configuration: Disabled (Enabled)

avhlza

Here are some links, it seems this notebook has given the same problems with others.

Link1
Link2

Edit: It seems like Link1 has the fix.
Link2 just shows there are issues with the dvd.

That worked perfectly.
Thank you very much mrrangerman! :D

Glad you got it working!!