Grub start problem

[corban dallas]

I have such configuration: prim master-hdd,win98,active, prim slave-hdd, secondary master-hdd,kubuntu, sec slave cdrom. I'll want move out hdd from primary slave, and remove cdrom on the this place one. I tried remove hdd, grub doesn't start. How i can make it? Thanks...

[dibl]

Re: Grub start problem

You can't -- the bootloader was on the Master Boot Record (MBR) of your primary/master hdd, so when you disable that drive, you disable Grub.

To replace that hdd, you will have to have Grub write a new bootloader. All the information you need is here:

http://kubuntuforums.net/forums/inde...opic=3081671.0

[corban dallas]

Re: Grub start problem

You are don't understand me right. I say in other words. I have: hda,hdb,hdd and hdc. On the hda i have win98 and mbr,hdd- linux system,hdc-cdrom, and hdb i want to remove. Its just hard drive with some data, when i disconnect him, grub don't start. Sent message error.

[corban dallas]

Re: Grub start problem

Message is error 21. ??

[dibl]

Re: Grub start problem

Hmmmmm. According to the Grub manual:

http://www.gnu.org/software/grub/manual/grub.html

This Error 21 means "selected disk does not exist". I can't imagine why it would throw that error unless that disk (or a partition on it) is trying to boot, i.e. it must be listed in your /boot/grub/menu.lst boot menu.

[corban dallas]

Re: Grub start problem

Thanks, i'm check check it now and report..... I'm turn on my pc...

[corban dallas]

Re: Grub start problem

So, there aren't any records about hdb! Nowhere. ?

[corban dallas]

Re: Grub start problem

I don't know, why does doing developers recheck nonactive partition by grub.... There're many manual operations from this... And so, i'll want to unit cdrom instead of hdb, how?

[Qqmike]

Re: Grub start problem

Your primary master should be your main, first drive, the one with Windows.
Then, (and I believe this is a rule for ATA interfaces) before filling up this first ATA interface (the primary slave), you should fill up both the secondary master and secondary slave.
The secondary master should be your Kubuntu drive, the secondary slave should be the CD ROM.

Is that how you have it?

Have you * manually * set the master and the slave jumpers? (That is, you are not using any Cable Select settings, right?)

dibl is correct about Error 21. In some menu, a “call” or a reference is made to some drive, and BIOS and GRUB cannot find the drive that’s being referenced.

Did you accidentally un-seat any cable? Try pressing all the ATA data-cable connections in real tight. It sounds like GRUB cannot see your Kubuntu drive now (?—maybe).

- - - - -
Also, you said last time that:
“I don't know, why does doing developers recheck nonactive partition by grub.... There're many manual operations from this... And so, i'll want to unit cdrom instead of hdb, how?”

Could you please explain what you mean a bit more?

[Qqmike]

Re: Grub start problem

. . . so, after checking the cables,

it may help to re-install GRUB using the How-To that dibl referenced.

Use your Kubuntu Live CD, open Konsole (a terminal), type
sudo grub
and press Enter, this gives you a grub prompt, grub>.

Use the geometry command (see the end of the How-To), to figure out exactly where your Kubuntu is -- as seen by your BIOS (and thus by GRUB):

grub> geometry (hd0)
and press Enter, and explore each drive this way
grub> geometry (hd1)
grub> geometry (hd2)
grub> geometry (hd3)

So far, this will tell you how BIOS and GRUB are seeing your hard drives and partitions.
(In GRUB, hard drives x and partitions y are numbered starting from zero. So your first hard drive, the first partition is (hd0,0); the second hard drive first partition is (hd1,0), etc.)

Now do this:
grub> find /boot/grub/stage1

(Note the space after the word “find”)

That will return some (hdx,y) telling you where the GRUB files are.
This may be (and usually is) the same as the partition of your Kubuntu OS.

Then re-install GRUB as follows:

grub> root (hdx,y)
grub> setup (hd0)
grub> quit
$ exit

(Note the space after “root” and the space after “setup”)

Then exit from your Live Kubuntu session and eject the Live CD.
Re-boot and see if it works.
(Make sure BIOS is set to boot from the hd0 Windows drive.)

In the above commands, note that

(hdx,y) is the hard drive and partition of your GRUB Stage_1 files (ie, the output from the “find” command above).;
and
(hd0) should be the hard drive of your Windows.

[corban dallas]

Re: Grub start problem

Fine!thanks. I have some job this night. I mean why grub recheck non active partition? If i disconect a hard drive for my needs, i'll need configure a system each time when i'm connect some ide device? Non active, certainly..

[corban dallas]

Re: Grub start problem

My bad hard drive was connected on the prim slave,and when i unplug its., i'll have trobles above. After that my prim slave is absent in the system. Jumpers setup are correct.

[Qqmike]

Re: Grub start problem

GRUB will read and try to follow what is in its configuration file, /boot/grub/menu.lst. (also called the boot menu). If you change a drive or a partition on that menu.lst, GRUB does not yet know that you changed things. It will still try to read and follow the boot menu.

If you re-install GRUB, it will start over – It will see the (new) drive arrangement the same way BIOS probes the drives and sees them.

Now, if you add a new drive that is not on the boot menu, GRUB will not see it and ignore it.

So, after you remove your IDE drive, and re-install GRUB (if necessary), you should be OK. If then later on, you connect that drive again (the one you removed), you should still be OK – GRUB will just ignore it.


You asked:
“I mean why grub recheck non active partition?”

Good question. I’m not exactly sure; maybe I need to think about it some more. And, fact is, we are not real sure what happened here yet. Did you check those data-cable connections? (There’s a saying in troubleshooting hardware: “It’s always the darned cables!”)

This is one use of the geometry command: it tells us exactly how BIOS & GRUB are seeing your drives. (By the way, GRUB sees the drives the same way BIOS sees them.)

[Qqmike]

Re: Grub start problem

"My bad hard drive was connected on the prim slave,and when i unplug its., i'll have trobles above. After that my prim slave is absent in the system. Jumpers setup are correct."

OK -- that is all OK (I think).
You can have Windows as the primary master, and then fill up the two slave interfaces. Check those cables.

And, finally, you may have to re-install GRUB (as above); use geometry to try to sort this out, too.

[dibl]

Re: Grub start problem

To help you think about what Qqmike has said:

Your BIOS is the "expert" on your system -- it give the hard drive layout to the OS kernel. In this regard, some BIOS/chipsets seem to be sensitive to whether the "boot" flag is set on the hard drive partition that you wish to boot Linux from. Others may not be sensitive. It definitely has to be set if you hope to boot Windows.

Your /etc/fstab table needs to be "truthful" -- it needs to reflect the drives and partitions that the OS reads from BIOS correctly, whether they are numbered by the conventional /dev/hd_ method or by UUID. You can check the running system with the command

blkid

and see what the OS thinks the drive/partition layout is.

Your /boot/grub/menu.lst file must match /etc/fstab, regarding the location of bootable OS's, except that Grub has a slightly different numbering system for the drives that you need to understand when you compare the two files. But they have to be consistent regarding the partition(s) where the bootable OS is located.