Upgrading a disk group

Prior to the release of Veritas Volume Manager 3.0, the disk group version was automatically upgraded (if needed) when the disk group was imported.

Note:

On some platforms, the first release of Veritas Volume Manager was 3.0 or 3.2.

From release 3.0 of Veritas Volume Manager, the two operations of importing a disk group and upgrading its version are separate. You can import a disk group from a previous version and use it without upgrading it.

When you want to use new features, the disk group can be upgraded. The upgrade is an explicit operation. Once the upgrade occurs, the disk group becomes incompatible with earlier releases of VxVM that do not support the new version.

Until the disk group is upgraded, it may still be deported back to the release from which it was imported.

Until completion of the upgrade, the disk group can be used "as is" provided there is no attempt to use the features of the current version. There is no "downgrade" facility. For disk groups which are shared among multiple servers for failover or for off-host processing, verify that the VxVM release on all potential hosts that may use the disk group supports the diskgroup version to which you are upgrading.

Attempts to use a feature of the current version that is not a feature of the version from which the disk group was imported results in an error message similar to this:

VxVM vxedit ERROR V-5-1-2829 Disk group version doesn't support
feature

To use any of the new features, you must run the vxdg upgrade command to explicitly upgrade the disk group to a version that supports those features.

All disk groups have a version number associated with them. Veritas Volume Manager releases support a specific set of disk group versions. VxVM can import and perform operations on a disk group of that version. The operations are limited by what features and operations the disk group version supports.

Table: Disk group version assignments summarizes the Veritas Volume Manager releases that introduce and support specific disk group versions.

Table: Disk group version assignments

VxVM release

Introduces disk group version

Supports disk group versions

1.2

10

10

1.3

15

15

2.0

20

20

2.2

30

30

2.3

40

40

2.5

50

50

3.0

60

20-40, 60

3.1

70

20-70

3.1.1

80

20-80

3.2, 3.5

90

20-90

4.0

110

20-110

4.1

120

20-120

5.0

140

20-140

5.1

150

20-150

Importing the disk group of a previous version on a Veritas Volume Manager system prevents the use of features introduced since that version was released.

Table: Features supported by disk group versions summarizes the features that are supported by disk group versions 20 through 150.

Table: Features supported by disk group versions

Disk group version

New features supported

Previous version features supported

150

SSD device support, migration of ISP dg

20, 30, 40, 50, 60, 70, 80, 90, 110, 120, 130, 140

140

Data migration, Remote Mirror, coordinator disk groups (used by VCS), linked volumes, snapshot LUN import.

20, 30, 40, 50, 60, 70, 80, 90, 110, 120, 130

130

  • VVR Enhancements

20, 30, 40, 50, 60, 70, 80, 90, 110, 120

120

  • Automatic Cluster-wide Failback for A/P arrays

  • Persistent DMP Policies

  • Shared Disk Group Failure Policy

20, 30, 40, 50, 60, 70, 80, 90, 110

110

  • Cross-platform Data Sharing (CDS)

  • Device Discovery Layer (DDL) 2.0

  • Disk Group Configuration Backup and Restore

  • Elimination of rootdg as a Special Disk Group

  • Full-Sized and Space-Optimized Instant Snapshots

  • Intelligent Storage Provisioning (ISP)

  • Serial Split Brain Detection

  • Volume Sets (Multiple Device Support for VxFS)

20, 30, 40, 50, 60, 70, 80, 90

90

  • Cluster Support for Oracle Resilvering

  • Disk Group Move, Split and Join

  • Device Discovery Layer (DDL) 1.0

  • Layered Volume Support in Clusters

  • Ordered Allocation

  • OS Independent Naming Support

  • Persistent FastResync

20, 30, 40, 50, 60, 70, 80

80

  • VVR Enhancements

20, 30, 40, 50, 60, 70

70

  • Non-Persistent FastResync

  • Sequential DRL

  • Unrelocate

  • VVR Enhancements

20, 30, 40, 50, 60

60

  • Online Relayout

  • Safe RAID-5 Subdisk Moves

20, 30, 40

50

  • SRVM (now known as Veritas Volume Replicator or VVR)

20, 30, 40

40

  • Hot-Relocation

20, 30

30

  • VxSmartSync Recovery Accelerator

20

20

  • Dirty Region Logging (DRL)

  • Disk Group Configuration Copy Limiting

  • Mirrored Volumes Logging

  • New-Style Stripes

  • RAID-5 Volumes

  • Recovery Checkpointing

To list the version of a disk group, use this command:

# vxdg list dgname

You can also determine the disk group version by using the vxprint command with the -l format option.

To upgrade a disk group to the highest version supported by the release of VxVM that is currently running, use this command:

# vxdg upgrade dgname

By default, VxVM creates a disk group of the highest version supported by the release. For example, Veritas Volume Manager 5.1 creates disk groups with version 150.

It may sometimes be necessary to create a disk group for an older version. The default disk group version for a disk group created on a system running Veritas Volume Manager 5.1 is 150. Such a disk group cannot be imported on a system running Veritas Volume Manager 4.1, as that release only supports up to version 120. Therefore, to create a disk group on a system running Veritas Volume Manager 5.1 that can be imported by a system running Veritas Volume Manager 4.1, the disk group must be created with a version of 120 or less.

To create a disk group with a previous version, specify the -T version option to the vxdg init command.