Administrator Guide

Adding single-ported disks to a disk group that contains dual-ported disks is supported. However, because single-ported disks are not
fault-tolerant, a confirmation prompt will appear.
NOTE: Expansion can take hours or days to complete, depending on the disk group's RAID level and size, disk speed,
utility priority, and other processes running on the storage system. You can stop expansion only by deleting the disk
group. For ADAPT disk groups, expansion is very fast and extra capacity is immediately available when rebalancing is not
needed. If rebalancing is needed, extra capacity may not be available until rebalancing is complete.
When disks are added to an ADAPT disk group, the system will first replenish any spare capacity needed to be fully fault-tolerant, then use
the remainder for expansion of user data capacity. When set to the default spare capacity, the system will try to replenish spare capacity
to be the sum of the largest two disks in the group.
• When default spare capacity has been overridden the system will try to replenish spare capacity to meet the configured target GiB.
For more information, see the topic about the add disk-group command in the Dell EMC PowerVault ME4 Series Storage System
CLI Guide.
• If the actual spare capacity meets the target spare capacity, the new disk capacity will be allocated to user data. For information on
how ADAPT disk groups manage sparing, see About RAID levels.
There are three sections that comprise the Expand Disk Group panel. The top section displays information about the disk group, including
its name, type, owner (controller), and data protection (RAID) level. The information that is based on the type of disk group being
expanded.
The middle section contains the disk selection sets summary and Disks table which presents cumulative data for existing disks and
dedicated spares in the disk group as well as for selected disks. The amount of disk space is color-coded to show total, available, dedicated
spares, and overhead disk space amounts.
The Disks table lists information about the disks and dedicated spares in the disk group, updating as you select disks to expand the disk
group to show the total number of disks selected and the total size of the disk group.
The bottom section lists the disks in each enclosure in your system, along with their details. Select the disks that you want to add to the
current disk group by doing one of the following:
• Select a range of disks within an enclosure by entering a comma-separated list that contains the enclosure number and disk range in
the Enter Range of Disks text box. Use the format enclosure-number.disk-range,enclosure-number.disk-range.
For example, to select disks 3-12 in enclosure 1 and 5-23 in enclosure 2, enter 1.3-12,2.5-23.
• Select all disks by checking the Select All checkbox.
• Filter the disks in the list per disk description, enclosure ID, slot location, or disk size by entering applicable search criteria in the text
box. Clear the filter by clicking the Clear Filters button.
• Click on individual disks within the table to select them and add them to the disk group.
Selected disks are highlighted in blue. To remove disks from the group, click on them the disks to deselect them.
Expand a disk group
1. In the Pools topic, select the pool for the disk group that you are expanding. Then select the disk group in the Expand Disk Group
table.
NOTE:
To see more information about a pool, hover the cursor over the pool in the table. Viewing pools contains
more details about the Pool Information panel that appears.
2. Select Action > Expand Disk Group. The Expand Disk Group panel opens displaying disk group information and disk tables.
3. For disk groups with RAID-10 or RAID-50 configurations, choose the number of new sub-groups in the Additional Sub-groups list.
4. Select additional disks that you want to add to the disk group from the table in the bottom section.
5. Click Modify. A confirmation panel appears.
6. Click Yes to continue. Otherwise click No. If you clicked Yes, the disk group expansion starts.
7. To close the confirmation panel, click OK.
Managing spares
The Manage Spares panel displays a list of current spares and lets you add and remove global spares for virtual and linear disk groups, and
dedicated spares for linear disk groups. The options in the panel are dependent on the type of disk group selected.
Working in the Pools topic
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