You can add hot spare disks to an aggregate to increase its size, so it can provide more storage space to its contained volumes. You might also want to increase the size of a specific RAID group.
Before You Begin
Make sure you understand the following concepts:
- Benefits of keeping your RAID groups homogenous for disk size and speed
- What types of disks can be used together (FCAL and SAS, SATA and ATA)
- How to add disks to aggregates from a heterogenous disk pool
- The requirement to add disks owned by the same system and pool
- Best practices for providing hot spares
- Checksum rules when zone checksum disks are present
Considerations
You can specify a RAID group to add disks to. If you do not specify a RAID group, the disks are added to the most recently created RAID group if there is room in that RAID group. Otherwise, a new RAID group is created.
To see the number and types of disks in each RAID group, you can use the aggr status -r command.
Steps
-
Verify that appropriate hot spare disks are available for you to add by entering the following command:aggr status -s
Make sure that enough of the spares listed are of the correct type, size, speed, checksum type, and disk connection architecture for the target RAID group in the aggregate to which you are adding the disks.
- Add the disks by entering the following command:aggr add aggr_name [-f] [-n] [-g {raid_group_name | new | all}] disk_list
-f enables you to add disks from a different pool or of a different speed.
-n displays the results of the command but does not execute it. This is useful for displaying the disks that Data ONTAP would automatically select. You can then decide whether to accept Data ONTAP's selection or to add different disks.
If you specify the -g option, the disks are added to the RAID group you specify. raid_group_name is the name that Data ONTAP gave to the group—for example, rg0.
To add the disks to a new RAID group, use the new keyword instead of the group name.
To fill all existing RAID groups to the current value of the raidsize option before creating a new RAID group, use the all keyword instead of the group name.
disk_list is one of the following parameters:
- ndisks[disk_size]
- -d disk1 [disk2...]
Examples
The following command adds four 300-GB disks to the aggr1 aggregate:aggr add aggr1 4@300
The following command adds the disks 5a.17 and 5a.26 to the rg1 RAID group of the aggr2 aggregate:aggr add aggr2 -g rg1 -d 5a.17 5a.26
The following command adds one disk to each plex of a mirrored aggregate aggr_mir:aggr add aggr_mir -d 5a.18 -d 8b.14
After You Finish
After you add disks to an aggregate, run a full reallocation job on each FlexVol volume contained in that aggregate. For information about reallocation, see your Block Access Management Guide.
