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

Chapter 7, Creating Volumes

Creating a Volume on Specific Disks

205

Specifying Ordered Allocation of Storage to Volumes

Ordered allocation gives you complete control of space allocation. It requires that the

number of disks that you specify to the vxassist command must match the number of

disks that are required to create a volume. The order in which you specify the disks to

vxassist is also significant.

If you specify the -o ordered option to vxassist when creating a volume, any storage

that you also specify is allocated in the following order:

1. Concatenate disks.

2. Form columns.

3. Form mirrors.

For example, the following command creates a mirrored-stripe volume with 3 columns

and 2 mirrors on 6 disks in the disk group, mydg:

# vxassist -b -g mydg -o ordered make mirstrvol 10g \

layout=mirror-stripe ncol=3 \

mydg01 mydg02 mydg03 mydg04 mydg05 mydg06

This command places columns 1, 2 and 3 of the first mirror on disks mydg01, mydg02 and

mydg03 respectively, and columns 1, 2 and 3 of the second mirror on disks mydg04,

mydg05 and mydg06 respectively. This arrangement is illustrated in “Example of Using

Ordered Allocation to Create a Mirrored-Stripe Volume.”

Example of Using Ordered Allocation to Create a Mirrored-Stripe Volume

Striped Plex

Mirror

Mirrored-Stripe

Volume

Column 1 Column 2 Column 3

mydg01-01 mydg02-01 mydg03-01

mydg04-01 mydg05-01 mydg06-01