Multi RedHat Distributions on one physical disk

[drakebasher]

I don't know if you've come across this, yet, but it sounds like you may since much in Fedora is carried over from Red Hat. Fedora Core uses the disk "label" to identify mounted partitions. During install, it labels each partition with a name corresponding to the mount point for the partition. For example, the partition which is to be mounted on mount point /boot/ will receive the label "/boot". Partitions can be labelled arbitrarily with the command e2label, but labels are not required on any partitions. In Fedora they show up in two places as far as I know: 1) in Grub, on the "kernel" line, something like: root=LABEL=/ and 2) in fstab where, in the first column you may other wise see /dev/hda2 Fedora will use the label something like: LABEL=/.

This is all well and good as long as there is not a conflict between two different installs, both using labels to reference the partitions. To avoid conflicts, either the labels created in the first install should be changed before the second install, or Grub and fstab should be edited to reference the /dev/ files directly instead of using labels.

[s.riccio]

Thanks for replying, I've been going craszy with this problem. I will try experimenting with the labels in /dev/files. I'll keep you posted

[s.riccio]

I think this is a RedHat issue. I think RedHat is looking for 3 parititions per installation; /boot, /, swap. I will experiment with this by creating these partitions for RedHat 7.3, 8.0 and 9.0 in partition 2 which will be an extended partition. Partition 1 will be /boot where I will eventually install GRUB to boot all 3

[drakebasher]

Sounds good. In Fedora Core, the separate /boot partition is not required. If you don't mount your shared /boot partition during installation of each install after the first, you won't risk anything in /boot getting stepped on. Then, after all is set up you can copy or move the kernel and initrd files for installs 2,3,4, etc from the /boot directory of their respective / partitions to the shared /boot partition, and at the same time, renaming or sym-linking each kernel and initrd to something recognizable.

[s.riccio]

Conclusion:
I finally got RedHat 7.3, 8.0, and 9.0 loaded onto one physical disk. I partitioned the disk into partition 1, 2 and 3. I made partition 2 a swap area for all versions. Partition 3 was configured as an extended partition with 4 logical partitions (the 4th will be for Fedora). Each install used an extended partition to mount only the root directory. I "did not" make a separate boot partition for each version (it became part of /). After everything was loaded I installed grub in partition 1. This was easy because each install produced a grub boot directory. I selectively updated partition 1/boot with initrd, vmlinuz from each version and configured grub.conf for all version of RedHat. I think RedHat helped me along the way by labeling the root directory to a unique name. I also think that you could probably place the swap partition in the extended paritition which I will try later. All seems to work.

[drakebasher]

Yeah, there's no problem with swap on an extended partition:

# fdisk -l

Disk /dev/hda: 20.5 GB, 20525137920 bytes
255 heads, 63 sectors/track, 2495 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hda1   *           1         123      987966    6  FAT16
/dev/hda2             124         489     2939895   83  Linux
/dev/hda3             490         612      987997+   6  FAT16
/dev/hda4             613        2495    15125197+   5  Extended
/dev/hda5             613        2495    15125166   83  Linux

Disk /dev/sda: 18.3 GB, 18389272576 bytes
255 heads, 63 sectors/track, 2235 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          10       80293+  83  Linux

/dev/sda2              11         137     1020127+  83  Linux
/dev/sda3             138         647     4096575   83  Linux
/dev/sda4             648        1451     6458130    5  Extended
/dev/sda5             648         711      514048+  83  Linux
/dev/sda6             712         834      987966   82  Linux swap
/dev/sda7             835         896      497983+  83  Linux
/dev/sda8             897        1383     3911796   83  Linux
/dev/sda9            1384        1445      497983+  83  Linux
/dev/sda10           1446        1451       48163+  83  Linux

Right now, I'm on hda5 and my swap is on sda6. I'd be interested in seeing your grub.conf when everything works.

[s.riccio]

Here is the output from and fdisk and the grub.conf to boot RedHat 7.3, 8.0, 9.0 and Solaris

-------------------------------------------------------------------------------------

fdisk /dev/hda

The number of cylinders for this disk is set to 19457.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
(e.g., DOS FDISK, OS/2 FDISK)

Command (m for help): p

Disk /dev/hda: 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/hda1 1 11 88326 83 Linux
/dev/hda2 12 19457 156199995 5 Extended
/dev/hda5 12 56 361431 82 Linux swap
/dev/hda6 57 4907 38965626 83 Linux
/dev/hda7 * 4908 9758 38965626 83 Linux
/dev/hda8 9759 14609 38965626 83 Linux
/dev/hda9 14610 19457 38941528+ 83 Linux

-------------------------------------------------------------------------------------
grub.conf

# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You do not have a /boot partition. This means that
# all kernel and initrd paths are relative to /, eg.
# root (hd0,6)
# kernel /boot/vmlinuz-version ro root=/dev/hda7
# initrd /boot/initrd-version.img
#boot=/dev/hda
default=0
timeout=10
splashimage=(hd0,6)/boot/grub/splash.xpm.gz

title Red Hat Linux - 7.3 (2.4.18-3)
root (hd0,6)
kernel /boot/vmlinuz-2.4.18-3 ro root=/dev/hda7
initrd /boot/initrd-2.4.18-3.img

title Red Hat Linux - 8.0 (2.4.18-14)
root (hd0,7)
kernel /boot/vmlinuz-2.4.18-14 ro root=/dev/hda8
initrd /boot/initrd-2.4.18-14.img

title Red Hat Linux - 9.0 (2.4.20-
root (hd0,
kernel /boot/vmlinuz-2.4.20-8 ro root=/dev/hda9
initrd /boot/initrd-2.4.20-8.img

title Solaris - 2.8
root (hd1,0)
chainload +1