100 SANRAD V-Switch User Manual
Creating a Mirrored Volume
Use mirroring to
create data backups.
The V-Switch
supports a maximum
of 512 volumes.
A mirrored volume is synchronously written into two or more volumes.
Mirrored volumes provide protection against data loss from a physical
disk crash. To be a true mirror and realize the full potential of a mirror,
the mirrored volumes must be located on different physical disks.
In Figure 47, data block 1 is mapped to both block 5 on Disk 1 and block 9
on Disk 2. Data blocks 2, 3 and 4 are mapped to both blocks 6,7 and 8 on
Disk 1 and blocks 10, 11 and 12 on Disk 2.
10024
Virtual
Volume
Physical
Volume
Mirrored
Volume
B1 B2 B3 B4
Disk 1
S10 S11
S9 S12
S6 S7
S5 S8
S14 S15
S13 S16
S2 S3
S1 S4
S10 S11
S9 S12
S6 S7
S5 S8
S14 S15
S13 S16
S2 S3
S1 S4
Disk 2
Figure 47. Mirrored Volume Block Distribution
volume create mirror
You need to define four parameters to create a mirrored volume:
SWITCH PARAMETER DEFINITION STATUS EXAMPLE
–vol
VOLUME ALIAS USER-ASSIGNED
ALAIS FOR THE
MIRRORED VOLUME
MANDATORY
Mirrored1
-nbc
NUMBER OF
CHILDREN
NUMBER OF
CHILDREN IN
MIRRORED VOLUME
OPTIONAL
DEFAULT: 2
MAX: 4
–ch
CHILD NAME OF EACH
CHILD TO INCLUDE
IN THE MIRROR
MANDATORY
Simple6
–ch
CHILD NAME OF EACH
CHILD TO INCLUDE
IN THE MIRROR
MANDATORY
Simple11
