[linux-lvm] root partition

[linux-lvm] root partition

[ramsis farhat]

Hello every body. I'm student and I have training in a company that wants to put LVM partitions in its server.
The problem is that they do not want to format the hard disk.
For the moment, I'm working on a virtual machine with Red Hat Entreprise 3.
I'm working with 2 hard disks of 8GB. The first is partitioned like this
sda1 boot (101 MB)
sda2 /      (7400MB)
sda3 swap (573 MB)
 
I followed exactly the steps in the LVM-HOWTO excepted that I added the second Hard disk sdb.
I made a lvm partion sdb1 and I put all the root data on it.
Then, I had 2 problems. The first is that the RAM disk can't be created because of the lack of space ( I'm not sure of that)
And the second is that the server is using GRUB and not LILO, so I don't know How rebooting on the new root file.
 
If anybody have any suggestion, and thank you for your help.

Re: [linux-lvm] root partition

[Dieter Stüken]

ramsis farhat wrote:
> Hello every body. I'm student and I have training in a company that wants to put LVM partitions in its server.
> The problem is that they do not want to format the hard disk.
> For the moment, I'm working on a virtual machine with Red Hat Entreprise 3.
> I'm working with 2 hard disks of 8GB. The first is partitioned like this
> sda1 boot (101 MB)
> sda2 /      (7400MB)
> sda3 swap (573 MB)
>  
> I followed exactly the steps in the LVM-HOWTO excepted that I added the second Hard disk sdb.
> I made a lvm partion sdb1 and I put all the root data on it.
> Then, I had 2 problems. The first is that the RAM disk can't be created because of the lack of space ( I'm not sure of that)
> And the second is that the server is using GRUB and not LILO, so I don't know How rebooting on the new root file.

What do you mean by "RAM disk"? Is it a problem while preparing the
ramdisk (initrd) by mkinited, or is it a problem to startup the
ramdisk during boot?

Both, grub and lilo need sda1 (/boot) to boot, load the kernel and
the initrd (ram disk). There are two things you should verify:
1) For the new root partition (more correct: root LV), be sure,
/boot still comes from /dev/sda1 (should be, as it was before).
2) the initrd (ram disk) created by mkinitrd, must know about
using LVM. This may be achieved either via some configuration
(my SuSE system looks into /etc/sysconfig/kernel) or by "-f lvm2".
See "man mkinitrd".

Dieter.

[linux-lvm] booting on a new root partition

[ramsis farhat]

Hello every body.
 
think you Dieter St�ken for you response.
I'm still working on a virtual machine with Red Hat Entreprise 3. So don't worry if I break it
I'm working with 2 hard disks of 8GB. The first is partitioned like this
sda1 boot (101 MB)
sda2 /      (7400MB)
sda3 swap (573 MB)
  
I followed exactly the steps in the LVM-HOWTO excepted that I added the second Hard disk sdb.
I made an lvm partion sdb1 and I put all the root data (size 6GB) on it. The new partition is /dev/vg00/root

Then, I had a problem : when I type "lvmcreate_initrd", the RAM disk can't be created because of the lack of space ( I'm not sure of that).
 
I used "lvmcreate_initrd  -D", the instruction returns 0 ( it means ok). But when I reboot, there is kernel panic.
so if I use initrd, i don't know if i need that!!!!!!!
 
Think you for helping me

Re: [linux-lvm] booting on a new root partition

[Dieter Stüken]

ramsis farhat wrote:
> I'm still working on a virtual machine with Red Hat Entreprise 3. So don't worry if I break it
> I'm working with 2 hard disks of 8GB. The first is partitioned like this
> sda1 boot (101 MB)
> sda2 /      (7400MB)
> sda3 swap (573 MB)
>   
> I followed exactly the steps in the LVM-HOWTO excepted that I added the second Hard disk sdb.
> I made an lvm partion sdb1 and I put all the root data (size 6GB) on it. The new partition is /dev/vg00/root
> 
> Then, I had a problem : when I type "lvmcreate_initrd", the RAM disk can't be created because of the lack of space ( I'm not sure of that).
>  
> I used "lvmcreate_initrd  -D", the instruction returns 0 ( it means ok). But when I reboot, there is kernel panic.
> so if I use initrd, i don't know if i need that!!!!!!!

I don't know about "lvmcreate_initrd", seems this is Redhad specific (I'm using SuSE).
I googled for it and found it should create some file:

/boot/initrd-lvm-<KernelVersion>.gz

is this created on your system? (May be your /boot partition is full?)
IF it was created, please verify, if it is referenced in your grub/lilo
configuration. Can you please post an "ls -ltr /boot", to show us the
content of your /boot partition and your grub or lilo configuration?

You also should edit the /etc/fstab of the new LVM-root change the name
of the new root partition/volume.

Dieter.

[linux-lvm] booting on a new root partition

[ramsis farhat]

hi everybody
Dieter, here is what you asked me
[root@localhost root]# ls -ltr /boot
total 6138
-rw-r--r--      1 root     root        21282      Sep 11  2003       message.ja
-rw-r--r--      1 root     root        23108      Sep 11  2003       message
-rw-r--r--      1 root     root        1236945   Oct  4  2003        vmlinuz-2.4.21-4.EL
-rw-r--r--      1 root     root        570887    Oct  4  2003        System.map-2.4.21-4.EL
-rwxr-xr-x    1 root     root        2900380  Oct  4  2003        vmlinux-2.4.21-4.EL
-rw-r--r--      1 root     root        543         Jul   30 21:30       kernel.h
-rw-r--r--      1 root     root        276990    Jul   30 21:30       initrd-2.4.21-4.EL.img
drwxr-xr-x   2 root     root        1024       Jul   30 21:43        grub
lrwxrwxrwx  1 root     root        22          Jul   30 21:43        System.map -> System.map-2.4.21-4.EL
drwx------     2 root     root        12288     Jul   30 23:26        lost+found
-rw-r--r--      1 root     root        48023      Aug  1 14:50         config-2.4.21-4.EL
-rw-r--r--      1 root     root        1154607  Aug  1 14:50         initrd-lvm-2.4.21-4.EL.gz
 
Her is my grub directory
 
[root@localhost root]# ls -ltr /boot/grub
total 185
-rw-r--r--    1 root     root        11182 Sep 11  2003 splash.xpm.gz
-rw-r--r--    1 root     root       106364 Jul 30 21:43 stage2
-rw-r--r--    1 root     root          512 Jul 30 21:43 stage1
lrwxr-xr-x    1 root     root           11 Jul 30 21:43 menu.lst -> ./grub.conf
-rw-r--r--    1 root     root           82 Jul 30 21:43 device.map
-rw-r--r--    1 root     root         9320 Jul 30 21:43 xfs_stage1_5
-rw-r--r--    1 root     root         6528 Jul 30 21:43 vstafs_stage1_5
-rw-r--r--    1 root     root         9408 Jul 30 21:43 reiserfs_stage1_5
-rw-r--r--    1 root     root         7040 Jul 30 21:43 minix_stage1_5
-rw-r--r--    1 root     root         8448 Jul 30 21:43 jfs_stage1_5
-rw-r--r--    1 root     root         6880 Jul 30 21:43 ffs_stage1_5
-rw-r--r--    1 root     root         7536 Jul 30 21:43 fat_stage1_5
-rw-r--r--    1 root     root         7840 Jul 30 21:43 e2fs_stage1_5
-rw-------    1 root     root          679 Aug  1 14:40 grub.conf

And here my configuration
 
[root@localhost root]# cat  /boot/grub/grub.conf
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE:  You have a /boot partition.  This means that
#          all kernel and initrd paths are relative to /boot/, eg.
#          root (hd0,0)
#          kernel /vmlinuz-version ro root=/dev/sda2
#          initrd /initrd-version.img
#boot=/dev/sda
default=0
timeout=10
splashimage=(hd0,0)/grub/splash.xpm.gz
title Red Hat Enterprise Linux ES (2.4.21-4.EL)
 root (hd0,0)
 kernel /vmlinuz-2.4.21-4.EL ro root=LABEL=/
 initrd /initrd-2.4.21-4.EL.img
title Ramsis
 root (hd0,0)
 kernel /vmlinuz-2.4.21-4.EL ro root=/dev/vg00/root
 initrd /initrd-lvm-2.4.21-4.EL.gz

 
And I mounted my new root ' mount /dev/vg00/root /mnt/ '
The new /etc/fstab contains : 
 
/dev/vg00/root          /                       ext3    defaults        1 1
LABEL=/boot             /boot                   ext3    defaults        1 2
none                    /dev/pts                devpts  gid=5,mode=620  0 0
none                    /proc                   proc    defaults        0 0
none                    /dev/shm                tmpfs   defaults        0 0
/dev/sda3               swap                    swap    defaults        0 0
/dev/cdrom              /mnt/cdrom              udf,iso9660 noauto,owner,kudzu,ro 0 0
/dev/fd0                /mnt/floppy             auto    noauto,owner,kudzu 0 0

But i still think the problrm is coming from the instruction "lvmcreate_initrd" because if I do not use the "-D" flag, the instruction fail, and in the "LVM-HOWTO", it is used without that flag.
If you have any suggestion :)
thank you :)

Re: [linux-lvm] booting on a new root partition

[Dieter Stüken]

ramsis farhat wrote:
> hi everybody
> Dieter, here is what you asked me
...
> But i still think the problrm is coming from the instruction "lvmcreate_initrd" > because if I do not use the "-D" flag, the instruction fail, and in the "LVM-HOWTO",
> it is used without that flag.
> If you have any suggestion :)

hi ramsis,

unfortunately no :-( looks all fine. But I dont use Redhat and I have
no idea what "lvmcreate_initrd" exactly does. Seems "-d" activates devfs
which is obsolete now. I also do not use 2.4 kernels any more.
I use a similar setup, but with SuSE 10.1 using an actual 2.6 kernel.

sorry
Dieter.