LVM Version 2.0 Volume Groups in HP-UX 11i v3 (September 2008)

Abstract ..............................................................................................................................................3
Audience ............................................................................................................................................3
Introduction .........................................................................................................................................3
What is a 2.x Volume Group? ...........................................................................................................3
How do I use a 2.x Volume Group?....................................................................................................3
What do I need to change to manage my 1.0 Volume Groups?.............................................................3
New Limits ..........................................................................................................................................4
LVM Changes in the March 2008 Release of HP-UX 11i v3 ......................................................................5
Creation of a volume group ...............................................................................................................5
Creation of a 1.0 volume group .....................................................................................................5
Creation of a 2.x volume group......................................................................................................5
Display of LVM Information................................................................................................................7
vgdisplay.....................................................................................................................................7
pvdisplay.....................................................................................................................................8
lvdisplay ......................................................................................................................................9
LVM Device Special Files.................................................................................................................10
lvmtab, lvmtab_p ............................................................................................................................11
New Command (lvmadm)................................................................................................................11
Summary List of New or Obsolete Commands Options .......................................................................12
Overview of Changes by Command .................................................................................................13
Other Differences Between Volume Group Versions 1.0 and 2.x..............................................................15
Sparing not supported on 2.x volume groups.....................................................................................15
Boot, dump and primary swap not supported on 2.x ..........................................................................15
Bad blocks not supported on 2.x ......................................................................................................15
Commands not supported on 2.x volume groups ................................................................................15
How to Provision a 2.x Volume Group..................................................................................................15
Simplified Provisioning ....................................................................................................................16
What is the Disadvantage of Over-Provisioning? ................................................................................16
Metadata size on disk versus maximum volume group size ..............................................................17
What are the Advantages of Over-Provisioning with 2.x?....................................................................17
2.x may leave as much space for user data on disk as 1.0..................................................................18
Impact of over-provisioning ..............................................................................................................19
How to Pick an Extent Size ..................................................................................................................19
Memory Footprint...............................................................................................................................21
Minimum Memory Footprint .............................................................................................................22
Maximum Memory Footprint ............................................................................................................23
Comparison of Volume Group Memory Footprints for the Same Number of Logical and Physical Volumes 24
How to Configure the New Limits .........................................................................................................26
Number of logical volumes or physical volumes in a volume group.......................................................26
Maximum size of the volume group ..................................................................................................26
Size of logical volume or number of mirrors.......................................................................................27
Migration Between1.0, 2.0 and 2.1 ....................................................................................................27
Why would a user migrate?.............................................................................................................27
How to migrate?.............................................................................................................................27
When to Migrate? ..........................................................................................................................27
High Availability ................................................................................................................................27
When Does it Make Sense to Use More Than Two Mirrors?.................................................................27
Glossary ...........................................................................................................................................30
For More Information..........................................................................................................................31
Call to Action ....................................................................................................................................31
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