Expanding a RAID

This section explains how to expand a RAID by adding segments to it.


Before you can expand the size of a RAID device, you must deactivate it.

Adding Mirrors to a RAID 1 Device

In a RAID 1 device, each member segment contains its own copy of all of the data stored in the RAID. You can add a mirror to the RAID to increase redundancy. The segment must be at least the same size as the smallest member segment in the existing RAID 1 device. Any excess space in the segment is not used. Ideally, all member segments of a RAID 1 device are the same size.

Adding an Available Segment as the New Mirror

Deactivate the RAID 1 device.
Use the Add Active (addactive plug-in) function.
From the list of available segments, select one that is the same size or larger than the smallest existing member of the RAID device.
Reactivate the RAID device.

Activating A Spare Disk as the New Mirror

If you have not set up a spare disk, do it now.
For information, see Section 6.4, “Adding or Removing a Spare Disk”.
Use the Activate Spare (activatespare plug-in) function to add it to the RAID 1 device as a new mirror.

Adding Segments to a RAID 4 or 5

If the RAID region is clean and operating normally, the kernel driver adds the new object as a regular spare, and it acts as a hot standby for future failures. If the RAID region is currently degraded, the kernel driver immediately activates the new spare object and begins synchronizing the data and parity information.