Creating an aggregate

You create an aggregate to provide disk space to one or more FlexVol volumes (or one traditional volume).

Before You Begin

Determine the name of the aggregate. Aggregate names must conform to the following requirements:

Begin with either a letter or an underscore (_)
Contain only letters, digits, and underscores
Contain no more than 250 characters

Note: You can change the name of an aggregate later by using the aggr rename command.

Determine what disks will be used in the new aggregate. You can specify disks by listing their IDs, or by specifying a disk characteristic such as speed or type. You can display a list of the available spares on your storage system by using the aggr status -s command.

Note: If your storage system is attached to more than one type of disk, and you do not use the -T option, Data ONTAP creates the aggregate using the disk type with the highest number of available disks. To ensure that Data ONTAP uses the disk type that you expect, always use the -T option when creating aggregates from a heterogeneous disk pool.

Step

Enter the following command:aggr create aggr_name [-f] [-m] [-n] [-t {raid4|raid_dp}] [-r raidsize] [-T disk-type] -R rpm] [-L] disk-list
aggr_name is the name for the new aggregate.

-f overrides the default behavior that does not permit disks in a plex to belong to different disk pools. This option also allows you to mix disks with different RPM speeds even if the appropriate raid.rpm option is not off.

-m specifies the optional creation of a SyncMirror-replicated volume if you want to supplement RAID protection with SyncMirror protection. A SyncMirror license is required for this feature.

-n displays the results of the command but does not execute it. This is useful for displaying the disks that would be automatically selected prior to executing the command.

-t{raid4 | raid_dp} specifies the level of RAID protection you want to provide for this aggregate. If no RAID level is specified, the default value (raid_dp) is applied.

-r raidsize is the maximum size of the RAID groups for this aggregate. If no size is specified, the default is used.

-T disk-type specifies one of the following types of disk to be used: ATA, SATA, SAS, or FCAL. This option is only needed when creating aggregates on systems that have mixed disks. Use FCAL for FC disks, ATA for ATA disks connected via FC-AL, SATA for SAS-attached ATA disks, and SAS for SAS-attached SAS disks.
Note: FCAL and SAS disks are considered to be the same type for the purposes of creating an aggregate. Similarly, ATA and SATA disks are considered to be the same type.

-R rpm specifies the type of disk to use based on its speed. Valid values for rpm include 5400, 7200, 10000, and 15000.

-L creates a SnapLock aggregate. For more information, see the na_aggr(1) man page or the Data Protection Online Backup and Recovery Guide.
disk-list is one of the following values:
- ndisks[@disk-size]
  ndisks is the number of disks to use. It must be at least 3 for RAID-DP aggregates or 2 for RAID-4 aggregates.
  
  disk-size is the disk size to use, in gigabytes.
- -d disk_name1 disk_name2... disk_nameN
  disk_name1, disk_name2, and disk_nameN are disk IDs of available disks; use a space to separate disk IDs.

Examples

The following command creates an aggregate called newaggr, with a RAID group size of 8, consisting of the disks with disk IDs 8a.16, 8a.17, 8a.18, and 8a.19:aggr create newaggr -r 8 -d 8a.16 8a.17 8a.18 8a.19

The following command creates an aggregate called newfastaggr, with 20 disks, the default RAID group size, and all disks with 15K RPM:aggr create newfastaggr -R 15000 20

The following command creates an aggregate called newFCALaggr. Note that if SAS disks are present, they might be used, because FC and SAS disks are considered to be the same type.aggr create newFCALaggr -T FCAL 15

After You Finish

You can use the aggr status -r command to verify the RAID groups and disks used in the aggregate you just created.

Parent topic: Managing aggregates

Related concepts

Considerations for sizing RAID groups

Protection provided by RAID and SyncMirror

How aggregates work

How Data ONTAP uses RAID to protect your data and data availability

How you can use disks with mixed speeds in the same aggregate