aggr create

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.
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
Increasing the size of an aggregate
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
1. 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.
2. Add the disks by entering the following command:aggr add aggr_name [-f] [-n] [-g raid_group_name] 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—e.g., rg0.
disk_list is one of the following parameters:
o ndisks[disk_size]
o -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.
• What happens when you add disks to an aggregate
By default, Data ONTAP adds new disks to the most recently created RAID group until it reaches its maximum size. Then Data ONTAP creates a new RAID group. Alternatively, you can specify a RAID group you want to add disks to.
• Forcibly adding disks to aggregates
You might want to override some of the restrictions on what disks can be added to an aggregate if you don't have disks of the right speed or enough disks in the correct pool. You use the aggr add -f command to accomplish this.
• What happens when you add disks to an aggregate that are larger than the existing disks
What Data ONTAP does when you add larger disks to an aggregate depends on the RAID level (RAID4 or RAID-DP) of the aggregate.
Taking an aggregate offline
You use the aggr offline command to take an aggregate offline to perform maintenance on the aggregate, move it, or destroy it.
Steps
1. If the aggregate you want to take offline contains FlexVol volumes, boot into maintenance mode.
Note: This step is not necessary for traditional volumes.
2. Enter the following command:aggr offline aggr_name
3. If you previously booted into maintenance mode, return to normal mode.
The aggregate is now offline. You cannot access any data in the aggregate's volumes.
Bringing an aggregate online
After you restrict an aggregate or take it offline, you can use the aggr online command to make it available to the storage system again by bringing it back online.
Enter the following command:aggr online aggr_name
If the aggregate is inconsistent, the command prompts you for confirmation.
Attention: If you bring an inconsistent aggregate online, it might suffer further file system corruption. If you have an inconsistent aggregate, contact technical support.
The aggregate is online and available for use.

Putting an aggregate into restricted state
You use the aggr restrict command to put the aggregate into a restricted state if you want the aggregate to be the target of an aggregate copy or SnapMirror replication operation.
Considerations
For information about aggregate copy and SnapMirror replication, see the Data Protection Online Backup and Recovery Guide.
Steps
1. If the aggregate you want to restrict contains FlexVol volumes, boot into maintenance mode.
Note: This step is not necessary for traditional volumes.
2. Enter the following command:aggr restrict aggr_name
3. If you previously booted into maintenance mode, return to normal mode.
The aggregate is now restricted. Data in the aggregate's volumes is unavailable to clients.
Parent topic: Managing aggregates
Determining how the space in an aggregate is being used
Not all of the disk space you add to an aggregate is available for user data. You use the aggr show_space command to display how the disk space in an aggregate is being used.
Considerations
If you specify the name of an aggregate, the command only displays information about that aggregate. Otherwise, the command displays information about all of the aggregates in the storage system.
For more information about the values returned by this command, see the na_aggr(1) man page.
Example
aggr show_space aggr1
Aggregate 'aggr1'

Total space WAFL reserve Snap reserve Usable space BSR NVLOG
33GB 3397MB 1529MB 28GB 0KB

Space allocated to volumes in the aggregate

Volume Allocated Used Guarantee
newvol 2344KB 2344KB (offline)
vol1 1024MB 1328KB volume
dest1 868KB 868KB volume

Aggregate Allocated Used Avail
Total space 1027MB 4540KB 27GB
Snap reserve 1529MB 6640KB 1522MB
WAFL reserve 3397MB 1280KB 3396MB
Destroying an aggregate
You destroy an aggregate when you no longer need the data in that aggregate or when you have copied the content of the aggregate to another location.
Before You Begin
Before you can destroy an aggregate, you must destroy all of the FlexVol volumes contained by that aggregate.
Considerations
When you destroy an aggregate, Data ONTAP converts its parity disks and all its data disks back into hot spares. You can then use the spares in other aggregates and other storage systems.
Attention: If you destroy an aggregate, the data in the aggregate is no longer accessible by normal access methods, unless you undestroy it before any of its disks are zeroed or reused in another aggregate.
Note: If you want to make the data in the aggregate inaccessible by any means, you can sanitize its disks.
Note: You cannot destroy a SnapLock Compliance aggregate until the retention periods for all data contained in it have expired. For more information about the SnapLock functionality, see the Data ONTAP Data Protection Online Backup and Recovery Guide
Steps
1. Take the aggregate offline by entering the following command:aggr offline aggr_name
2. Destroy the aggregate by entering the following command:aggr destroy aggr_name
The following message is displayed:
Are you sure you want to destroy this aggregate ?
3. Enter the following command to confirm that you want to destroy the aggregate:y
The following message is displayed:Aggregate 'aggr_name' destroyed.
hanging an aggregate's RAID level from RAID4 to RAID-DP
Before you change an aggregate’s RAID protection from RAID4 to RAID-DP, you need to ensure that enough appropriate hot spare disks are available.
Steps
1. Determine the number of RAID groups and the size of their parity disks in the aggregate in question by entering the following command:aggr status aggr_name -r
2. List the available hot spares on your system by entering the following command:aggr status -s
3. Make sure that at least one, and preferably two hot spare disks exist for each RAID group listed. If necessary, add additional hot spare disks.
4. Enter the following command:aggr options aggr_name raidtype raid_dp
When you change the RAID level of an aggregate from RAID4 to RAID-DP, Data ONTAP makes the following changes:
• Adds an additional disk to each existing RAID group from the storage system’s hot spare disk pool; assigns the new disk the dParity disk function for the RAID-DP group. A reconstruction begins for each RAID group to populate the dParity disk.
• Changes the raidsize option for the aggregate to the appropriate RAID-DP default value.
Undestroying an aggregate
If you previously destroyed an aggregate and have changed your mind, you can undestroy the aggregate if the data is still intact and the aggregate was not SnapLock-compliant.
Before You Begin
You must know the name of the aggregate you want to undestroy, because there is no Data ONTAP command available to display destroyed aggregates, nor do they appear in FilerView.
Undestroy the aggregate by entering the following command:aggr undestroy aggr_name
Example
sys1> aggr undestroy aggr1
The following message is displayed:To proceed with aggr undestroy, select one of the following options [1] abandon the command [2] undestroy aggregate aggr1 ID: 0xf8737c0-11d9c001-a000d5a3-bb320198 Selection (1-2)?
If you select 2, a message with a date and time stamp appears for each disk that is restored to the aggregate. The last line of the message says:Aggregate ‘aggr1’ undestroyed. Run wafliron to bring the aggregate online.
After You Finish
After undestroying an aggregate, you must run the wafliron program with the privilege level set to advanced. If you need assistance, contact technical support.
•
Note: You can change the raidsize option after the RAID level change is complete.
After You Finish
You can verify the new RAID level by using the aggr options command.
Changing an aggregate's RAID level from RAID-DP to RAID4
When you change an aggregate's RAID level from RAID-DP to RAID4, the extra parity disks are converted to spares. In addition, the raidsize option is changed.
Enter the following command:aggr options aggr_name raidtype raid4
When you change the RAID level of an aggregate from RAID4 to RAID-DP, Data ONTAP makes the following changes:
• In each of the aggregate’s existing RAID groups, the RAID-DP second parity disk (dParity) is removed and placed in the hot spare disk pool, thus reducing each RAID group’s size by one parity disk.
• Data ONTAP changes the setting for the aggregate’s raidsize option to the size of the largest RAID group in the aggregate, except in the following situations:
o If the aggregate’s largest RAID group is larger than the maximum RAID4 group size, then the aggregate’s raidsize option is set to the maximum.
o If the aggregate’s largest RAID group is smaller than the default RAID4 group size, then the aggregate’s raidsize option is set to the default group size.
o If the aggregate's raidsize option is already below the default value for RAID4, it is reduced by 1.
After You Finish
You can verify the new RAID level by using the aggr options command.
Physically moving an aggregate
To move an aggregate from one storage system (the source) to another (the target), you need to physically move disks, disk shelves, or entire loops or stacks. You might move an aggregate to move data to a new storage system model or remove data from an impaired storage system.
Before You Begin
Ensure that the target storage system meets the following requirements:
• It must be running a version of Data ONTAP that is the same or later than the version running on the source system.
• It must support the shelf, module, and disk types being moved.
• It must support the size of the aggregate being moved.
Considerations
The procedure described here applies to both aggregates with FlexVol volumes and to traditional volumes.
The procedure described here does not apply to V-Series systems. For information about how to physically move aggregates in V-Series systems, see the V-Series Software Setup, Installation, and Management Guide.
Steps
1. In normal mode, enter the following command at the source storage system to locate the disks that contain the aggregate:aggr status aggr_name -r
The locations of the data, parity, and dParity disks in the aggregate appear under the HA, SHELF, and BAY columns (dParity disks appear for RAID-DP aggregates only).
2. Complete the appropriate steps, depending on whether you are moving an aggregate or a traditional volume.
If you are moving... Then...
A traditional volume Take the volume offline by entering the following command:aggr offline vol_name
An aggregate a. Boot the storage system into maintenance mode.
b. Take the aggregate offline by entering the following command:aggr offline aggr_name
3. Follow the instructions in the disk shelf hardware guide to remove the disks or shelves you identified previously from the source storage system.
4. Install the disks or disk shelves in the target storage system.
When the target storage system sees the new disks, it sees the new aggregate as a foreign aggregate. Data ONTAP takes the foreign aggregate offline. If the foreign aggregate has the same name as an existing aggregate on the target storage system, Data ONTAP renames it aggr_name(1), where aggr_name is the original name of the aggregate.
5. If the target storage system uses software-based disk ownership, assign the disks that you moved to the target storage system by entering the following command for each moved disk:disk assign disk_name
6. Confirm that the foreign aggregate is complete by entering the following command:aggr status aggr_name
Attention: If the foreign aggregate is incomplete (if it has a status of partial), add all missing disks before proceeding. Do not try to add missing disks after the aggregate comes online—doing so causes them to become hot spare disks. You can identify the disks currently used by the aggregate using the aggr status -r command.
7. If the storage system renamed the foreign aggregate because of a name conflict, enter the following command to rename the aggregate:aggr rename aggr_name new_name
8. Enter the following command to bring the aggregate online in the destination storage system:aggr online aggr_name
9. Enter the following command to confirm that the added aggregate came online:aggr status aggr_name
10. Boot both source storage systems out of maintenance mode.
For more information about maintenance mode, see the Data ONTAP System Administration Guide.