[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.