## Increasing free space

Using this feature you can add one, two, or three physical hard disk drives to an existing array so you can create another logical drive in the array.

When you create an array, logical drives are striped across all physical drives in that array. To create more free space in an existing array, define additional physical drives to add to the array. Then, the Manager migrates the logical drives such that the data is spread across the existing and new physical drives.

1. Click an array from the Main Tree (that is, the left tree).

2. Click Actions --> Increase free space. Another tree displays on the right.
3. Add to the selected array by dragging ready drives from the Main Tree to the array in the right tree.

   Notes:

   1. The Main Tree displays only physical drives that are at least the size of the smallest physical drive in the selected array. When adding to an existing array, you cannot add physical drives that are smaller than the smallest drive currently in the array.
   2. When adding to an existing array, if you add physical drives that are larger than the physical drives currently in the array, you will not be able to use all the space on the new drives.
   3. Existing physical drives in the selected array are labeled online. Newly added physical drives are labeled new online. You cannot remove online drives from an existing array.
   4. If you want to remove a new online drive from the array, drag it back to the Main Tree.

4. After you add the physical drives to your arrays, click Next to review your new logical drive configuration.

5. Review the configuration in the right panel. It describes how the configuration will affect the logical drives and free space when you click Apply. If you want to modify the configuration, click Back to return to the array tree window.

   Tip: You can expand the tree for another view of the configuration.

6. Click Apply to approve the new configuration. The Manager automatically migrates the logical drives in the array.
   If you do not want to approve the logical drive configuration, click Cancel and return to the system management information window.

   Note: Logical drive migration is a lengthy process. You cannot perform any other actions on the affected controller until the migration is complete. The ServeRAID Manager displays a progress indicator in the status bar.

7. Click Yes when the confirm pop-up window opens.

### Example

Create an array with three physical drives. Then, create two logical drives (labeled as 1 and 2) in the array such that you have no available free space. The logical drive stripes look similar to the following.

Later, you decide to create another logical drive in the array. First, you must create some free space by adding more physical hard disk drives to the array.

If you add two more physical hard disk drives to the array, the logical drives migrate such that they are striped across all five drives. The ServeRAID Manager retains the size of the logical drive by decreasing the size of each block on a physical drive. The space in the logical drives does not increase, so there is free space across the bottom portion of each physical drive (labeled as 3).

When the operation is complete, use the Configuration mode to create a new logical drive in the free space.

When increasing free space, you can add up to three physical drives, as long as the sum of the physical drives does not exceed the maximum number of physical drives allowed for the array. The maximum number of physical drives you can have in an array is limited by the controller stripe-unit size.

### See also

- Working with physical drives and arrays during logical drive migration