VERITAS Volume Manager 3.5 User's Guide - VERITAS Enterprise Administrator (June 2002)

Chapter 4, Volume Tasks 89
Creating a Dynamic Volume
RAID-5
A RAID-5 volumespreads across two ormore disks, and contains parity information. You
have the option of placing a file system on the new volume.
Layout: Choose RAID-5 for the volume layout.
In the Number of Columns field, specify the number of columns
(disks) across which the volume should be striped. A RAID-5
volume requires at least three disks (or four disks if logging is
enabled).
To specify a stripe unit size other than the default, enter the stripe
unit size in the Stripe Unit Size field. To specify a size unit, attach
an s (sectors), k (kilobytes), m (megabytes), or g (gigabytes) to the
size.
Options:
- To place a file system on the volume, click Create a file
system and specify the file system type and mount point in
the New File System dialog box.
- To enable RAID-5 logging for the volume, select Enable
Logging. VxVM adds an appropriate number of logs to the
volume.
- To clear the volume before enabling it for general use, select
Initialize Zero.
Notes:
- A RAID-5 volume requires at least three disks. If logging is enabled, a RAID-5 volume
requires at least four disks.
- RAID-5 volumes cannot be mirrored.
- For a RAID-5 volume, thesize specifiedin theSize field is the usable space in the volume.
Volume Manager allocates additional space for the volume parity information. The disks
across which the RAID-5 volume is striped must, therefore, contain additional free space
for the volume parity information.
- If no disks are assigned, VxVM uses available space on disks in the selected disk group.
- If afilesystem is placed on the volume andthe Mount at Boot option isselected,the file
system table file is automatically updated.