Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

redundancy and access to those objects. VxVM detects I/O failures on objects and
relocates the affected subdisks. The subdisks are relocated to disks designated as
spare disks or to free space within the disk group. VxVM then reconstructs the
objects that existed before the failure and makes them accessible again.
When a partial disk failure occurs (that is, a failure affecting only some subdisks
on a disk), redundant data on the failed portion of the disk is relocated. Existing
volumes on the unaffected portions of the disk remain accessible.
See “How hot-relocation works” on page 406.
Volume sets
Volume sets are an enhancement to VxVM that allow several volumes to be
represented by a single logical object. All I/O from and to the underlying volumes
is directed via the I/O interfaces of the volume set. The Veritas File System (VxFS)
uses volume sets to manage multi-volume file systems and the SmartTier feature.
This feature allows VxFS to make best use of the different performance and
availability characteristics of the underlying volumes. For example, file system
metadata can be stored on volumes with higher redundancy, and user data on
volumes with better performance.
See “Creating a volume set” on page 386.
Understanding Veritas Volume Manager
Volume sets
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