Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

To dissociate a version 0 DCO object, DCO volume and snap objects from the

volume, use the following command:

# vxassist [-g diskgroup] remove log volume logtype=dco

To upgrade the volume, use the following command:

# vxsnap [-g diskgroup] prepare volume [ndcomirs=number] \

[regionsize=size] [drl=on|sequential|off] \

[storage_attribute ...]

The ndcomirs attribute specifies the number of DCO plexes that are created

in the DCO volume. You should configure as many DCO plexes as there are

data and snapshot plexes in the volume. The DCO plexes are used to set up a

DCO volume for any snapshot volume that you subsequently create from the

snapshot plexes. For example, specify ndcomirs=5 for a volume with 3 data

plexes and 2 snapshot plexes.

The regionsize attribute specifies the size of the tracked regions in the

volume. A write to a region is tracked by setting a bit in the change map. The

default value is 64k (64KB). A smaller value requires more disk space for the

change maps, but the finer granularity provides faster resynchronization.

To enable DRL logging on the volume, specify drl=on (this is the default

setting). If you need sequential DRL, specify drl=sequential. If you do not

need DRL, specify drl=off.

To define the disks that can or cannot be used for the plexes of the DCO

volume, you can also specify vxassist-style storage attributes.

Setting tags on volumes

Volume tags implement Storage Foundation's SmartTier feature. You can also

apply tags to vsets using the same vxvm command syntax as shown below.

See the Veritas Storage Foundation Advanced Features Administrator’s Guide.

The following forms of the vxassist command let you do the following:

■ Set a named tag and optional tag value on a volume.

■ Replace a tag.

■ Remove a tag from a volume.

Administering volumes

Setting tags on volumes

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