Hi David,
You can add the disk drives to the enclosure, one at a time with ~1 minute wait is a good idea. After each insertion check Array Config Utility-->Physical View to verify the new drives.
After that, you may assign each of the new drives to their corresponding array, you should use the ACU User Guide at:
http://docs.hp.com/en/9320/acu.pdf , page 24
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1. Click Controller Settings, and verify that the Expand Priority setting is acceptable.
2. Back up all data on the array. Although array expansion is unlikely to cause data loss, observing
this precaution provides additional data protection.
3. Click Expand array, and then click Begin.
4. Choose the array that you want to expand, and then click Next.
5. Select the physical drives that you want to add to the array, and then click Next.
6. Click Finish to accept the changes.
At this point (before clicking Save in the next step), you can create logical drives on the unused
space created by the expansion. You can also arrange to expand another array on the same
controller by repeating the previous steps. However, the controller can expand only one array at a
time. Remaining array expansions are queued.
7. Click Save.
The controller now rearranges (re-stripes) the existing logical drives and their data so that they
extend over all the physical drives in the enlarged array.
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Finally double check your OS compatibility *before* doing a Logical Drive Extension.
Hope it helps,
Sergio
