VERITAS Volume Manager 3.5 Installation Guide (August 2002)

Chapter 5, Getting Started with VxVM

System Setup Guidelines

RAID-5 Guidelines

Note The VxVM Full license is required to use this feature.

Refer to the following guidelines when using RAID-5. For more information, see the

VERITAS Volume Manager Administrator’s Guide.

In general, the guidelines for mirroring and striping together also apply to RAID-5. The

following guidelines should also be observed with RAID-5:

◆ Only one RAID-5 plex can exist per RAID-5 volume (but there can be multiple log

plexes).

◆ The RAID-5 plex must be derived from at least two subdisks on two or more physical

disks. If any log plexes exist, they must belong to disks other than those used for the

RAID-5 plex.

◆ RAID-5 logs can be mirrored and striped.

◆ If the volume length is not explicitly speciﬁed, it is set to the length of any RAID-5

plex associated with the volume; otherwise, it is set to zero. If you specify the volume

length, it must be a multiple of the stripe unit size of the associated RAID-5 plex, if

any.

◆ If the log length is not explicitly speciﬁed, it is set to the length of the smallest RAID-5

log plex that is associated, if any. If no RAID-5 log plexes are associated, it is set to

zero.

◆ Sparse RAID-5 log plexes are not valid.