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Subject: Re: [linux-lvm] On-disk and LVM internal metadata representation
From: Dave Wysochanski <dwysocha@redhat.com>
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Date: Mon, 05 Mar 2007 11:12:23 -0500
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On Mon, 2007-03-05 at 04:54 -0700, Nallammai S wrote:
> Hi,
> 
> Whats the difference between on-disk metadata and LVM  internal representation? How does LVM map between these two representations?
> 
> Thanks in advance.
> 
> Nallammai.S 
> 

It is different for LVM1 vs LVM2.

LVM2
- text-based on-disk metadata
- format-specific code in lib/format_text

LVM1
- binary on-disk metadata
- format-specific code in lib/format1

If you read the import*.[ch] and export*.[ch] files in the format
specific directories you will get an understanding of the mapping.  I
also found following the label_read() function to be helpful.