Logical Volume Management
LinuxTag
Friday 5th May 2006
Alasdair Kergon
agk@redhat.com
Logical Volume Management
Advantages of LVM
What is Device Mapper?
Userspace Architecture
Device Mapper Kernel Architecture
Mapped Devices
Snapshot
Original Logical Volume
Add Copy On Write Logical Volume
Insert Snapshot Layers
Read a Block from Origin
Read a Block from Snapshot
Write a Block to Origin(1) – Notify Snapshot
Write a Block to Origin (2) – Write
Write a Block to Origin – Summary
Write Any Block to Snapshot
Read a Changed Snapshot Block
Single Snapshot Summary
Two Snapshots
Mirror
Mirror – pvmove
Mirror – pvmove – Before
Mirror – pvmove – After
Mirror – pvmove - During
libdevmapper
Tools
Some LVM commands
Metadata
Metadata – On-disk Layout
Metadata - Label
Metadata – Label Data for LVM2 001
Metadata – Metadata Area
Metadata – Updating Metadata(1)
Metadata – Updating Metadata(2)
Metadata – Versioning
Metadata
Metadata (2)
Text Metadata Format (1)
Text Metadata Format (2)
vgconvert
LVM2 Tool Enhancements (1)
LVM2 Tool Enhancements (2)
LVM2 Tool Enhancements (3)
LVM2 Tool Enhancements (4)
Caching
Allocation
vgreduce --removemissing
Reporting – pvs, lvs, vgs
Reporting – pvs, lvs, vgs(2)
Configuration files
Tagging
Tagging – Object Tags
Tagging – Host Tags
Tagging – Controlling Activation
Tagging – Simple Example
Clustering
segment types
Mirrors
dmsetup
Device-mapper Roadmap – Core (1)
Device-mapper Roadmap – Core (2)
Device-mapper Roadmap – Targets
Device-mapper Roadmap – Targets
Device-mapper Roadmap – Multipath
Device-mapper Roadmap - Clustering
Links