< Previous  | TOC | Index | Next  >

Creating volumes by specifying capabilities

A capability is a high-level description of a volume, for example, DataMirroring, Striping or PrefabricatedRaid5. ISP automatically selects a suitable template from those that provide the desired capability. As such, this is the most abstract way of creating volumes using vxassist as it requires the least specification by you. You can customize a capability by specifying values for any variable parameters that it defines.

Many predefined capabilities are supported.

See Capability.

Creating a mirrored volume

The following command creates a 1 GB volume with the default number of two mirrors:

# vxassist -g mydg -P mypool make mir2vol 1g \

  capability='DataMirroring' init=active

The init=active attribute makes the volume immediately available for use without attempting to synchronize its empty plexes.

The following command creates a 1 GB volume with three mirrors:

# vxassist -g mydg -P mypool make mir3vol 1g \

  capability='DataMirroring(nmirs=3)' init=active

Creating a mirrored volume with mirrors on separate enclosures

The following command creates a 2 GB mirrored volume with two mirrors, and with the mirrors located on separate enclosures:

# vxassist -g mydg -P mypool make strpvol 2g \

  capability='DataMirroring,MirrorsOnSeparateComponents'

Such a volume tolerates the failure of one enclosure and provides greater reliability.

Such a capability can be combined with multipathing to provide resilience against the failure of one of the paths to an enclosure, for example, in the following command:

# vxassist -g mydg -P mypool make strpvol 2g \

  capability='DataMirroring,MirrorsOnSeparateComponents,\

MultipathingThroughMultiplePaths'

Creating a striped volume

The following command creates a 2 GB striped volume with 10 columns:

# vxassist -g mydg -P mypool make strpvol 2g \

  capability='Striping(ncols=10)'

Creating a mirrored-stripe volume with mirrors on separate controllers

The following command creates a 2 GB mirrored-stripe volume with eight columns, and with the mirrors located on separate controllers:

# vxassist -g mydg -P mypool make strpvol 2g \

  capability='DataMirrorStripe(ncols=8),\

MirrorsOnSeparateComponents(component="Controller")'

Creating a striped-mirror volume from prefabricated mirrors

The following command creates a 10 GB striped-mirror volume with eight columns, and which uses prefabricated mirrors that are exported by an array to form each column:

# vxassist -g mydg -P mypool make strpvol 2g \

  capability='Striping(ncols=8),PrefabricatedDataMirroring'

Creating a RAID-5 volume with a RAID-5 log

The following command creates a 2 GB RAID-5 volume with eight data columns and a RAID-5 log that has two redundant copies:

# vxassist -g mydg -P mypool make r5vol 2g \

  capability='Raid5Capability(ncols=8),\

Raid5LogMirroring(nlogs=2)'