D.2. Metadata Contents
The volume group metadata contains:
- Information about how and when it was created
- Information about the volume group:
The volume group information contains:
- Name and unique id
- A version number which is incremented whenever the metadata gets updated
- Any properties: Read/Write? Resizeable?
- Any administrative limit on the number of physical volumes and logical volumes it may contain
- The extent size (in units of sectors which are defined as 512 bytes)
- An unordered list of physical volumes making up the volume group, each with:
- Its UUID, used to determine the block device containing it
- Any properties, such as whether the physical volume is allocatable
- The offset to the start of the first extent within the physical volume (in sectors)
- The number of extents
- An unordered list of logical volumes. each consisting of
- An ordered list of logical volume segments. For each segment the metadata includes a mapping applied to an ordered list of physical volume segments or logical volume segments
