Hierarchical consistency groups enable you to manage large workloads spanning multiple volumes, creating a parent consistency group that serves as an umbrella for child consistency groups.

Hierarchical consistency groups have a parent that can include up to five individual consistency groups. Hierarchical consistency groups can support different local Snapshot policies across consistency groups or individual volumes. If you use a remote protection policy, that will apply for the entire hierarchical consistency group (parent and children).

Beginning with ONTAP 9.13.1, you can modify the geometry of your consistency groups and move volumes between child consistency groups.

For object limits on consistency groups, see Object limits for consistency groups.

Create a hierarchical consistency group with new LUNs or volumes

When creating a hierarchical consistency group, you can populate it with new LUNs. Beginning with ONTAP 9.13.1, you can also use new NVMe namespaces and NAS volumes.

ONTAP System Manager

Steps

Select Storage > Consistency groups.
Select +Add then select the protocol for your storage object.

In ONTAP 9.10.1 through 9.12.1, the only option for a new storage object is Using new LUNs. Beginning with ONTAP 9.13.1, ONTAP System Manager supports creating consistency groups with new NVMe namespaces and new NAS volumes.
Name the consistency group. Designate the number of volumes or LUNs and the capacity per volume or LUN.
1. Application Type: If you are using ONTAP 9.12.1 or later, select an application type. If no value is selected, the consistency group will be assigned the type of Other by default. Learn more about tagging consistency in Application and component tags. If you plan to use a remote protection policy, you must choose Other.
Select the host operating system and LUN format. Enter the host initiator information.
1. For New LUNs: Select the host operating system and LUN format. Enter the host initiator information.
2. For New NAS volumes: choose the appropriate export option (NFS or SMB/CIFS) based on the NAS configuration of your SVM.
3. For New NVMe namespaces: Select the host operating system and NVMe subsystem.
To add a child consistency group, select More options then +Add child consistency group.
Select the performance level, the number of LUNs or volumes, and capacity per LUN or volume. Designate the appropriate export configurations or operating system information based on the protocol you are using.
Optionally, select a local snapshot policy and set the access permissions.
Repeat for up to five child consistency groups.
Select Save.
Confirm your consistency group has been created by returning to the main consistency group menu where it will appear once the ONTAP job completes. If you set a protection policy, look under the appropriate policy, remote or local, which should display a green shield with a checkmark in it.

CLI

Before you begin

You must be at the admin privilege level to perform this task.
In ONTAP 9.14.1, you must be a cluster or SVM administrator to perform this task. Beginning with ONTAP 9.15.1, any user at the admin privilege level can perform this task.

Step

Create the new consistency group using the consistency-group create command.

The volume-count parameter sets the number of volumes in each child consistency group. You can create a parent consistency group with a maximum of five child consistency groups.

consistency-group create -vserver SVM_name -consistency-group consistency_group_name -parent-consistency-group parent_consistency_group_name -cg-count number_of_child_consistency_groups -volume volume_prefix -volume-count number -size size -export-policy policy_name -storage-service extreme

Create a hierarchical consistency group with existing volumes

You can organize existing volumes into a hierarchical consistency group.

ONTAP System Manager

Steps

Select Storage > Consistency groups.
Select +Add then Using existing volumes.
Select the storage VM.
Select the existing volumes to include. Only volumes that are not already part of a consistency group will be available for selection.
To add a child consistency group, select +Add Child Consistency Group. Create the necessary consistency groups, which will be named automatically.
1. Component Type: If you are using ONTAP 9.12.1 or later, select a component type of "data", "logs", or "other". If no value is selected, the consistency group will be assigned the type of Other by default. Learn more about tagging consistency in Application and component tags. If you plan to use a remote protection policy, you must use Other.
Assign existing volumes to each consistency group.
Optionally, select a local Snapshot policy.
Repeat for up to five child consistency groups.
Select Save.
Confirm your consistency group has been created by returning to the main consistency group menu where it will appear once the ONTAP job completes. If you have chosen a protection policy, confirm it was properly set by selecting your consistency group from the menu; under the appropriate policy type, you will see a green shield with a checkmark inside of it.

CLI

Beginning with ONTAP 9.14.1, you can create an hierarchical consistency group using the CLI.

Before you begin

You must be at the admin privilege level to perform this task.
In ONTAP 9.14.1, you must be a cluster or SVM administrator to perform this task. Beginning with ONTAP 9.15.1, any user at the admin privilege level can perform this task.

Steps

Provision a new parent consistency group and assign volumes to a new child consistency group:

consistency-group create -vserver svm_name -consistency-group child_consistency_group_name -parent-consistency-group parent_consistency_group_name -volumes volume_names
Enter y to confirm you want to create a new parent and child consistency group.

Next steps