Re: Moving boot

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Karl Larsen wrote:
Les Mikesell wrote:
Karl Larsen wrote:

I now have the /boot part of my whole system. But it would be easy to make a new partition of say 100 MB the first thing on the second hard drive. My question is what do I need to do so the new /boot works?

I did something similar with a dual-boot system:  Windows on the
original first drive, all by itself.  And Linux installed on an added
second drive, all by itself.

While setting up GRUB, you define its root (where /boot/ is) with a
"root (hd1,0)", then "setup (hd0)" which puts the bootloader onto the
first drive MBR, and quit out of the GRUB shell.

[root@bigblack ~]# grub
grub> root (hd1,0)
grub> setup (hd0)
grub> quit
[root@bigblack ~]#

In this scenario, the computer boots, reads the MBR on my first drive,
which starts off GRUB from my second drive.

I believe that you can even set that up from within the GRUB start up
screen. Just hit the right hot key to get into the command line. You
can also do it from the rescue disc, so you can get a system working
that's not currently booting.

I know Tim and that is what I use now that works. I have grub at (hd0) and the Linux is at (hd1,5). This works fine so why move /boot?

I am certain that (hd1,5) is about 100 GB up from start of the second drive. And it works.

I thought this whole thread was about this setup not working all the time. What does fdisk -l say about the cylinder range of that 5th partition?

   Well it is the sixth partition. This is (hd1,5) in grub talk :-)


Disk /dev/sdb: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

  Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *           1        1217     9775521   83  Linux
/dev/sdb2            1218        1945     5847660   83  Linux
/dev/sdb3 1946 1961 128520 82 Linux swap / Solaris
/dev/sdb4            1962       18534   133122622+   5  Extended
/dev/sdb5            1962        7060    40957686   83  Linux
/dev/sdb6            7061       12159    40957686   83  Linux
/dev/sdb7           12160       18534    51207156   83  Linux
[root@k5di ~]#

Now you can see sdb6 starts at cylinder 7061 which the hell and gone above 1100 :-(


So thanks for the idea for quantizing the fact. I think it's clear my 1994 BIOS works far better than the so-called standard. 8-)

The hard drive addressing limits in bios have evolved slowly and painfully over time starting from 32 Megs in DOS. The next limit after 1024 cylinders was a 24 bit LBA address which would take you to around 128 gigs. http://en.wikipedia.org/wiki/Logical_Block_Addressing

I didn't do the math, but that error message you posted leaves no doubt that you are exceeding the bios limit when you can't boot so your 6th partition must span that range. But, regardless of what the limit actually turns out to be, you could have easily avoided any such problem by putting a small /boot at the beginning of the disk, something that has been well known since the first drives over 9 gigs were manufactured.

Les you do not read what I wrote.

I read what you wrote when you quoted the explicit bios error message.

Again, my /boot is 7,000 cylinders from the start of hard drive 2

As I pointed out, there have been other limits as bios evolved to match available hard disks.

and the grub is on hard drive 1 MBR

A tiny part of grub is there. Several other stages are elsewhere.


AND IT WORKS JUST FINE! NO PROBLEM AT ALL.

Then how did you get that error message about exceeding a bios limit to display? And why have you been complaining about it for days?

--
  Les Mikesell
   lesmikesell@xxxxxxxxx


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