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I had a mirrored array with 2 * 1TB drives. I have replaced both drives (one at a time and allowed it to rebuid) with 2 * 2TB drive. So I now have a capacity of 2TB rather than 1TB. However, the array is now reporting to have 1.8TB of unused space. How do I allocated the new unused disk space to this array?


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Please take a look at the HP Smart Array Reference Manual and its section on Array Expansion and Migration.

In short, you have the concept of an Array (the assembly of the physical disks) and a Logical Drive (logical RAID arrays within the physical Array).

Your current setup has a Logical Drive of 1TB in RAID 1. Your unused space can be used to extend the existing Logical Drive, or to carve out a new Logical Drive.

If you are doing this using the HP Array Configuration Utility (web interface), you can follow the prompts to expand the array. The space will be available to Windows, but you'll have to handle the partitioning at that level.

This also depends on your controller's setup, though. The Smart Array P212 controller can only do this online if you have a battery-backed cache (BBWC) unit installed.

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Hi, Thanks for your reply. However, I don't see 'expand array' as an available task when using the ACU web interface. - Does this mean it isn't available? could it be done via the CLI? or from BIOS? regards – Kip Aug 20 '12 at 7:51
This won't be an option unless you have a cache battery on the controller. – ewwhite Aug 20 '12 at 11:22
How can I check if I have a battery? the rebuild of the array was done online. - I have another array on the same controller which has the O/s and this rebuilt array holds only DATA. - Does that suggest there is battery? – user132760 Aug 20 '12 at 13:42
@user132760- The battery is in a black plastic housing and is connected to the controller by a cable. If you pop the cover on your system, you should be able to tell fairly easily if there's a battery attached. You can also also get battery status information from ACU (see the Smart Array user's guide for details). – bta Sep 20 '12 at 23:54

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