Information Technology Reference
In-Depth Information
Hot Spare Pools
A
hot spare pool
is a collection of slices that are automatically substituted for
slices that fail. When a disk error occurs, SVM locates a
hot spare
(slice) in the
hot spare pool that is at least the size of the failing slice and allocates the hot
spare as a replacement for the failing slice. Assuming a RAID 1 (mirrored) or
RAID 5 configuration, the data from the failed slice is copied to its replace-
ment from the mirrored data or rebuilt using parity information.
Disk Sets
A
disk set
or
shared disk set
is the combination of volumes with a State
Database, one or more State Database Replicas, and Hot Spares that can be
shared between two or more host systems. However, only one host system
can use the disk set at a time.
The purpose of the disk set is to provide data availability for a cluster of host
systems. That is, if one host system fails, another host in the system can take
over its operations. The disk set provides a means for all the clustered host
systems to share and access the same data. This is referred to as a
failover
configuration
.
Administration of SVM Objects
Two methods are available to manage the SVM objects. The first is the
Enhanced Storage Tool
, which provides a graphical user interface. This is
accessible via the
Solaris Management Console
. The second is a set of com-
mands that are referred to collectively as the SVM
command-line interface
.
Enhanced Storage Tool
The Enhanced Storage Tool is used to set up and administer the SVM con-
figuration. It provides a graphical view of both the SVM objects and the
underlying physical disks. The SVM configuration can be modified quickly
by using drag-and-drop manipulation.
SVM Command-Line Interface
The command-line interface provides a set of commands to create and man-
age SVM objects. Most of these commands start with the prefix “meta” such
as the
metainit
command used to initialize a volume. The command-line
interface includes the following commands:
growfs(1M)
—Expands a UFS file system
➤
metaclear(1M)
—Deletes volumes and hot spare pools
➤
