[linux-lvm] grub and lvm

[linux-lvm] grub and lvm

[rich turner]

i have a volume group built on a physical volume that is the
disk /dev/hdb. when i write the grub bootloader to that disk, it appears
that the bootloader overwrites part or all of the lvm data on that disk,
essentially wiping out my volume group. does anyone know if that is
normal or if lvm and grub indeed share the same place on the disk?

Re: [linux-lvm] grub and lvm

[rich turner]

an additional question, does lvm write anything into the mbr when a disk
is used as a physical volume, as opposed to a partition?

On Mon, 2005-06-06 at 09:13 -0700, rich turner wrote:
> i have a volume group built on a physical volume that is the
> disk /dev/hdb. when i write the grub bootloader to that disk, it appears
> that the bootloader overwrites part or all of the lvm data on that disk,
> essentially wiping out my volume group. does anyone know if that is
> normal or if lvm and grub indeed share the same place on the disk?
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@redhat.com
> https://www.redhat.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/

Re: [linux-lvm] grub and lvm

[Alan Jurgensen]

You may want to create a Linux LVM partition, and using that in lvm 
(pvcreate /dev/hdb1)...


rich turner wrote:

>i have a volume group built on a physical volume that is the
>disk /dev/hdb. when i write the grub bootloader to that disk, it appears
>that the bootloader overwrites part or all of the lvm data on that disk,
>essentially wiping out my volume group. does anyone know if that is
>normal or if lvm and grub indeed share the same place on the disk?
>
>_______________________________________________
>linux-lvm mailing list
>linux-lvm@redhat.com
>https://www.redhat.com/mailman/listinfo/linux-lvm
>read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
>  
>

-- 

----------------------------------------------------------------------
Alan W. Jurgensen - Berbee Information Networks - jurgensen@berbee.com 

Re: [linux-lvm] grub and lvm

[rich turner]

using a partition works fine. but i am trying to understand why i can't
write my grub bootloader to a disk that is being used as a physical
volume. is grub and lvm using the same part of the disk for its own use?


On Mon, 2005-06-06 at 11:36 -0500, Alan Jurgensen wrote:
> You may want to create a Linux LVM partition, and using that in lvm 
> (pvcreate /dev/hdb1)...
> 
> 
> rich turner wrote:
> 
> >i have a volume group built on a physical volume that is the
> >disk /dev/hdb. when i write the grub bootloader to that disk, it appears
> >that the bootloader overwrites part or all of the lvm data on that disk,
> >essentially wiping out my volume group. does anyone know if that is
> >normal or if lvm and grub indeed share the same place on the disk?
> >
> >_______________________________________________
> >linux-lvm mailing list
> >linux-lvm@redhat.com
> >https://www.redhat.com/mailman/listinfo/linux-lvm
> >read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
> >  
> >
> 

Re: [linux-lvm] grub and lvm

[rich turner]

for what it is worth ...

i have found that you can only write the grub boot loader to a disk that
is partitioned. perhaps something they will fix in grub2.

On Mon, 2005-06-06 at 09:50 -0700, rich turner wrote:
> using a partition works fine. but i am trying to understand why i can't
> write my grub bootloader to a disk that is being used as a physical
> volume. is grub and lvm using the same part of the disk for its own use?
> 
> 
> On Mon, 2005-06-06 at 11:36 -0500, Alan Jurgensen wrote:
> > You may want to create a Linux LVM partition, and using that in lvm 
> > (pvcreate /dev/hdb1)...
> > 
> > 
> > rich turner wrote:
> > 
> > >i have a volume group built on a physical volume that is the
> > >disk /dev/hdb. when i write the grub bootloader to that disk, it appears
> > >that the bootloader overwrites part or all of the lvm data on that disk,
> > >essentially wiping out my volume group. does anyone know if that is
> > >normal or if lvm and grub indeed share the same place on the disk?
> > >
> > >_______________________________________________
> > >linux-lvm mailing list
> > >linux-lvm@redhat.com
> > >https://www.redhat.com/mailman/listinfo/linux-lvm
> > >read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
> > >  
> > >
> > 
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@redhat.com
> https://www.redhat.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/

Re: [linux-lvm] grub and lvm

[Dan Stromberg]

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Just a guess, but maybe what you're seeing is grub's inability to read
LVM partitions?

ISTR that grub has built-in knowledge of common linux filesystems, which
is why you don't have to rerun grub like you do with lilo - because ISTR
that lilo is saving a list of blocks to read somewhere for boot time, so
that it won't need filesystem knowledge.

But I wouldn't be surprised a bit of an ext3 over LVM2 isn't represented
on-disk differently from just ext3, which might mean that grub would
need LVM2 knowledge.

Just a totally-wild-guess.  HTH.

On Mon, 2005-06-06 at 09:50 -0700, rich turner wrote:
> using a partition works fine. but i am trying to understand why i can't
> write my grub bootloader to a disk that is being used as a physical
> volume. is grub and lvm using the same part of the disk for its own use?
> 
> 
> On Mon, 2005-06-06 at 11:36 -0500, Alan Jurgensen wrote:
> > You may want to create a Linux LVM partition, and using that in lvm 
> > (pvcreate /dev/hdb1)...
> > 
> > 
> > rich turner wrote:
> > 
> > >i have a volume group built on a physical volume that is the
> > >disk /dev/hdb. when i write the grub bootloader to that disk, it appears
> > >that the bootloader overwrites part or all of the lvm data on that disk,
> > >essentially wiping out my volume group. does anyone know if that is
> > >normal or if lvm and grub indeed share the same place on the disk?
> > >
> > >_______________________________________________
> > >linux-lvm mailing list
> > >linux-lvm@redhat.com
> > >https://www.redhat.com/mailman/listinfo/linux-lvm
> > >read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
> > >  
> > >
> > 
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@redhat.com
> https://www.redhat.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
> 

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Re: [linux-lvm] grub and lvm

[Eric M. Hopper]

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On Mon, 2005-06-06 at 09:50 -0700, rich turner wrote:
> using a partition works fine. but i am trying to understand why i can't
> write my grub bootloader to a disk that is being used as a physical
> volume. is grub and lvm using the same part of the disk for its own use?

Yes.  Grub uses the same sectors as are used by the partition table.
So, even if this 'limitation' were removed, you wouldn't get even one
sector of extra space.

Have fun (if at all possible),
-- 
The best we can hope for concerning the people at large is that they
be properly armed.  -- Alexander Hamilton
-- Eric Hopper (hopper@omnifarious.org  http://www.omnifarious.org/~hopper) --

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