Skip to main content

Modify consistency group geometry

Contributors netapp-ahibbard netapp-aaron-holt

Beginning with ONTAP 9.13.1, you can modify the geometry of a consistency group. Modifying the geometry of a consistency group enables you to alter the configuration of child or parent consistency groups without disruption to ongoing IO operations.

Modifying consistency group geometry has an impact on existing snapshots of the consistency group. For details, refer to the specific modification to geometry you want to perform.

Note You cannot modify the geometry of a consistency group that is configured with a remote protection policy. You must first break the protection relationship, modify the geometry, then restore remote protection.

Add a new child consistency group

Beginning with ONTAP 9.13.1, you can add a new child consistency group to an existing parent consistency group.

About this task
  • A parent consistency group can contain a maximum of five child consistency groups. See consistency group limits for other limits.

  • You cannot add a child consistency group to a single consistency group. You must first promote the consistency group, then you can add a child consistency group.

  • Existing snapshots of the consistency group captured before the expand operation will be considered partial. Any restore operation based on that snapshot will reflect the consistency group at the point-in-time of the snapshot.

Beginning with ONTAP 9.13.1, you can perform this operation with System Manager.

Add a new child consistency group
  1. Select Storage > Consistency groups.

  2. Select the parent consistency group you want to which you want to add a child consistency group.

  3. Next to the parent consistency group's name, select More then Add new child consistency group.

  4. Enter a name for your consistency group.

  5. Choose whether you would like to add new or existing volumes.

    1. If you are adding existing volumes, select Existing volumes then choose the volumes from the dropdown menu.

    2. If you are adding new volumes, select New volumes then designate the number of volumes and their size.

  6. Select Add.

Detach a child consistency group

Beginning with ONTAP 9.13.1, you can remove a child consistency group from its parent, converting it into an individual consistency group.

About this task
  • Detaching a child consistency group causes the parent consistency group's snapshots to become invalid and inaccessible. Volume granular snapshots remain valid.

  • Existing snapshots of the individual consistency group remain valid.

  • This operation will fail if there is an existing single consistency group that has the same name as the child consistency group you intend to detach. If you encounter this scenario, you must rename the consistency group when you detach it.

Beginning with ONTAP 9.13.1, you can perform this operation with System Manager.

Detach a child consistency group
  1. Select Storage > Consistency groups.

  2. Select the parent consistency group that contains the child you want to detach.

  3. Next to the child consistency group you want to detach, select More then Detach from parent.

  4. Optionally, rename the consistency group and select an application type.

  5. Select Detach.

Move an existing single consistency group under a parent consistency group

Beginning with ONTAP 9.13.1, you can convert an existing single consistency group to a child consistency group. You can either move the consistency group under an existing parent consistency group or create a new parent consistency group during the move operation.

About this task
  • The parent consistency group must have four or fewer children. A parent consistency group can contain a maximum of five child consistency groups. See consistency group limits for other limits.

  • Existing snapshots of the parent consistency group captured before this operation are considered partial. Any restore operation based on one of those snapshots reflects the consistency group at the point-in-time of the snapshot.

  • Existing consistency group snapshots of the single consistency group remain valid.

Beginning with ONTAP 9.13.1, you can perform this operation with System Manager.

Move an existing single consistency group under a parent consistency group
  1. Select Storage > Consistency groups.

  2. Select the consistency group you want to convert.

  3. Select More then Move under different consistency group.

  4. Optionally, enter a new name for the consistency group and select a component type. By default, the component type will be Other.

  5. Choose if you want to migrate to an existing parent consistency group or create a new parent consistency group:

    1. To migrate to an existing parent consistency group, select Existing consistency group then choose the consistency group from the dropdown menu.

    2. To create a new parent consistency group, select New consistency group then provide a name for the new consistency group.

  6. Select Move.

Promote a child consistency group

Beginning with ONTAP 9.13.1, you can promote a single consistency group to a parent consistency group. When you promote the single consistency group to a parent, you also create a new child consistency group that inherits all of the volumes in the original, single consistency group.

About this task
  • If you want to convert a child consistency group to a parent consistency group, you must first detach the child consistency group then follow this procedure.

  • Existing snapshots of the consistency group remain valid after you promote the consistency group.

Beginning with ONTAP 9.13.1, you can perform this operation with System Manager.

Promote a child consistency group
  1. Select Storage > Consistency groups.

  2. Select the consistency group you want to promote.

  3. Select More then Promote to parent consistency group.

  4. Enter a Name and select a Component type for the child consistency group.

  5. Select Promote.

Demote a parent to a single consistency group

Beginning with ONTAP 9.13.1, you can demote a parent consistency group to a single consistency group. Demoting the parent flattens the hierarchy of the consistency group, removing all associated child consistency groups. All volumes in the consistency group will remain under the new, single consistency group.

About this task
  • Existing snapshots of the parent consistency group remain valid after you demote it to a single consistency. Existing snapshots of any of the associated child consistency groups of that parent become invalid upon demotion. The individual volume snapshots within the child consistency group continue to be accessible as volume-granular snapshots.

Beginning with ONTAP 9.13.1, you can perform this operation with System Manager.

Demote a consistency group
  1. Select Storage > Consistency groups.

  2. Select the parent consistency group you want to demote.

  3. Select More then Demote to single consistency group.

  4. A warning will advise you that all associated child consistency groups will be deleted and their volumes will be moved under the new single consistency group. Select Demote to confirm you understand the impact.