Expanding a logical unit using the CLI

You can use the command-line interface (CLI) to expand a logical unit.

Some storage systems enable you to expand the size of a logical unit (LU) using vendor-specific disk-configuration software that is provided. The steps in this procedure are required for the SAN Volume Controller to use extra capacity that is provided in this way.

To ensure that this additional capacity is available to the SAN Volume Controller, follow these steps:

  1. Issue the svctask rmmdisk CLI command to remove the managed disk (MDisk) from the MDisk group. Use the force parameter to migrate data on the specified MDisk to other MDisks in the group. The command completes asynchronously if -force is specified. You can check the progress of active migrations by running the svcinfo lsmigrate command.
  2. Use the vendor-specific, disk-configuration software to expand the size of the logical unit on the storage system.
  3. Issue the svctask detectmdisk CLI command to rescan the fibre-channel network. The rescan discovers any changes to existing MDisks and any new MDisks that have been added to the cluster. This command completes asynchronously and might take a few minutes. To determine whether a discovery operation is still in progress, use the svcinfo lsdiscoverystatus command.
  4. Issue the svcinfo lsmdisk CLI command to display the additional capacity that has been expanded.
  5. Issue the svctask addmdisk CLI command to add the MDisk back to the group.

The extra capacity is available for use by the SAN Volume Controller.

Parent topic: Configuring and servicing storage systems
Related tasks
Adding MDisks to MDisk groups
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