VERITAS Volume Manager 3.5 Administrator's Guide (September 2002)

Chapter 1, Understanding VERITAS Volume Manager

Volume Layouts in VxVM

Striped-Mirror Volume Laid out on Six Disks

See “Creating a Striped-Mirror Volume” on page 175 for information on how to create a

striped-mirrored volume.

As shown in the ﬁgure, “How the Failure of a Single Disk Affects Mirrored-Stripe and

Striped-Mirror Volumes,” the failure of a disk in a mirrored- stripe layout detaches an

entire data plex, thereby losing redundancy on the entire volume. When the disk is

replaced, the entire plexmust be brought up to date. Recovering the entire plex can take a

substantial amount of time. If a disk fails in a striped-mirror layout, only the failing

subdisk must be detached, and only that portion of the volume loses redundancy. When

the disk is replaced, only a portion of the volume needs to be recovered. Additionally, a

mirrored-stripe volume is more vulnerable to being put out of use altogether should a

second disk fail before the ﬁrst failed disk has been replaced, either manually or by

hot-relocation.

Striped Plex

Mirror

Striped-Mirror

Volume

Underlying Mirrored Volumes

Column 1 Column 2 Column 3