Veritas Volume Manager 4.1 Administrator's Guide (HP-UX 11i v3, February 2007)

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 215 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” on page 28, 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 plex must 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 0 Column 1 Column 2