Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

245Creating volumes
Creating a striped volume
# vxassist -b -g mydg make stripevol 30g layout=stripe \
stripeunit=32k ncol=5
Creating a mirrored-stripe volume
A mirrored-stripe volume mirrors several striped data plexes.
Note: A mirrored-stripe volume requires space to be available on at least as many disks in
the disk group as the number of mirrors multiplied by the number of columns in the
volume.
To create a striped-mirror volume, use the following command:
# vxassist [-b] [-g diskgroup] make volume length \
layout=mirror-stripe [nmirror=number_mirrors] \
[ncol=number_of_columns] [stripewidth=size]
Alternatively, first create a striped volume, and then mirror it as described in “Adding a
mirror to a volume” on page 263. In this case, the additional data plexes may be either
striped or concatenated.
Creating a striped-mirror volume
A striped-mirror volume is an example of a layered volume which stripes several
underlying mirror volumes.
Note: A striped-mirror volume requires space to be available on at least as many disks in
the disk group as the number of columns multiplied by the number of stripes in the
volume.
To create a striped-mirror volume, use the following command:
# vxassist [-b] [-g diskgroup] make volume length \
layout=stripe-mirror [nmirror=number_mirrors] \
[ncol=number_of_columns] [stripewidth=size]
By default, VxVM attempts to create the underlying volumes by mirroring subdisks rather
than columns if the size of each column is greater than the value for the attribute
stripe-mirror-col-split-trigger-pt that is defined in the
vxassist
defaults file.
If there are multiple subdisks per column, you can choose to mirror each subdisk
individually instead of each column. To mirror at the subdisk level, specify the layout as
stripe-mirror-sd rather than stripe-mirror. To mirror at the column level,
specify the layout as stripe-mirror-col rather than stripe-mirror.