Creating a consistency group does not automatically enable protection. Protection policies can be set at the time of creation or after creating your consistency group. You can protect consistency groups using:

Local Snapshot policies
SnapMirror Business Continuity (SM-BC)
MetroCluster (beginning 9.11.1)
Asynchronous SnapMirror (beginning 9.13.1)

If you are utilizing nested consistency groups, you can set different protection policies for the parent and child consistency groups.

Beginning with ONTAP 9.11.1, consistency groups offer two-phase consistency group Snapshot creation. The two-phase Snapshot operation executes a pre-check, ensuring the Snapshot copy is captured successfully.

Recovery can occur for an entire consistency group, a single consistency group in a hierarchical configuration, or for individual volumes within the consistency group. Recovery can be achieved by selecting the consistency group you want to recover from, selecting the Snapshot copy type, and then identifying the Snapshot copy to base the restoration on. For more information about this process, see Restore a volume from an earlier Snapshot copy.

Configure a local Snapshot policy

Setting a local snapshot protection policy allows you to create a policy spanning all volumes in a consistency group.

About this task

The minimum supported Snapshot copy schedule for consistency groups is 30 minutes.

ONTAP System Manager

Steps

Select Storage > Consistency groups.
Select the consistency group you have created from the Consistency group menu.
At the top right of the overview page for the consistency group, select Edit.
Check the box next to Schedule Snapshot copies (local).
Select a Snapshot policy. To configure a new, custom policy, refer to Create a custom data protection policy.
Select Save.
Return to the consistency group overview menu. In the left column under Snapshot Copies (Local), the status will say protected next to .

Create an on-demand Snapshot copy

If you need to create a Snapshot copy of your consistency group outside of a normally scheduled policy, you can create one on-demand.

ONTAP System Manager

Steps

Navigate to Storage > Consistency groups.
Select the consistency group for which you want to create an on-demand Snapshot copy.
Switch to the Snapshot copies tab then select +Add.
Provide a Name and a SnapMirror Label. In the dropdown menu for Consistency, select Application consistent or Crash consistent.
Select Save.

Create two-phase consistency group snapshots

Beginning with ONTAP 9.11.1, consistency groups support two-phase commits for consistency group (CG) Snapshot creation, which execute a precheck before committing the Snapshot copy. This feature is only available with the ONTAP REST API.

Two-phase CG Snapshot creation is only available for Snapshot creation, not provisioning consistency groups or restoring consistency groups.

A two-phase CG Snapshot breaks the Snapshot creation process into two phases:

In the first phase, the API executes prechecks and triggers Snapshot creation. The first phase includes includes a timeout parameter, designating the amount of time for the Snapshot copy to commit successfully.
If the request in phase one completes successfully, you can invoke the second phase within the designated interval from the first phase, committing the Snapshot copy to the appropriate endpoint.

Before you begin

To use two-phase CG Snapshot creation, all nodes in the cluster must be running ONTAP 9.11.1 or later.
Only one active invocation of a consistency group Snapshot operation is supported on a consistency group instance at a time, whether it be a one-phase or two-phase. Attempting to invoke a Snapshot operation while another one is in progress results in a failure.
When you invoke the Snapshot creation, you can set an optional timeout value of between 5 and 120 seconds. If no timeout value is provided, the operation times out at the default of 7 seconds. In the API, set the timeout value with the action_timeout parameter. In the CLI, use the -timeout flag.

Steps

You can complete a two-phase Snapshot with the REST API. This operation is not supported in System Manager.

If you invoke the Snapshot creation with the API, you must commit the Snapshot copy with the API.

API

Invoke the Snapshot creation. Send a POST request to the consistency group endpoint using the action=start parameter.

curl -k -X POST 'https://<IP_address>/application/consistency-groups/<cg-uuid>/snapshots?action=start&action_timeout=7' -H "accept: application/hal+json" -H "content-type: application/json" -d '
{
  "name": "<snapshot_name>",
  "consistency_type": "crash",
  "comment": "<comment>",
  "snapmirror_label": "<SnapMirror_label>"
}'

If the POST request succeeds, the output includes a Snapshot uuid. Using that uuid, submit a PATCH request to commit the Snapshot copy.

curl -k -X PATCH 'https://<IP_address>/application/consistency-groups/<cg_uuid>/snapshots/<snapshot_id>?action=commit' -H "accept: application/hal+json" -H "content-type: application/json"

Set remote protection for a consistency group

Consistency groups offer remote protection through SM-BC and, Beginning with ONTAP 9.13.1, asynchronous SnapMirror.

Configure protection with SM-BC

You can utilize SM-BC to ensure Snapshot copies of consistency groups created on your consistency group are copied to the destination. To learn more about SM-BC, refer to Configure protection for business continuity.

Before you begin

SM-BC relationships cannot be established on volumes mounted for NAS access.
The policy labels in the source and destination cluster must match.
SM-BC will not replicate Snapshot copies by default unless a rule with a SnapMirror label is added to the predefined AutomatedFailOver policy and the Snapshot copies are created with that label.

To learn more about this process, refer to Protect with SM-BC.
Cascade deployments are not supported with SM-BC.
Beginning with ONTAP 9.13.1, you can non-disruptively add volumes to a consistency group with an active SM-BC relationship. Any other changes to a consistency group require you to break the SM-BC relationship, modify the consistency group, then reestablish and resynchronize the relationship.

To configure SM-BC with the CLI, see Protect with SM-BC.

Steps for System Manager

Ensure you have met the prerequisites for using SM-BC.
Select Storage > Consistency groups.
Select the consistency group you have created from the Consistency group menu.
At the top right of the overview page, select More then Protect.
ONTAP System Manager auto-fills source-side information. Select the appropriate cluster and storage VM for the destination. Select a protection policy. Ensure that Initialize relationship is checked.
Select Save.
The consistency group needs to initialize and synchronize. Confirm synchronization has completed successfully by returning to the Consistency group menu. The SnapMirror (Remote) status displays Protected next to .

Configure asynchronous SnapMirror protection

Beginning with ONTAP 9.13.1, you can configure asynchronous SnapMirror protection for a single consistency group.

Before you begin

Asynchronous SnapMirror protection is only available for single consistency groups. It is not supported for hierarchical consistency groups. To convert a hierarchical consistency group into a single consistency group, see modify consistency group architecture.
Cascade deployments are not supported with SM-BC.
The policy labels in the source and destination cluster must match.
You can non-disruptively add volumes to a consistency group with an active asynchronous SnapMirror relationship. Any other changes to a consistency group require you to break the SnapMirror relationship, modify the consistency group, then reestablish and resynchronize the relationship.
If you have configured an asynchronous SnapMirror protection relationship for multiple individual volumes, you can convert those volumes into a consistency group while retaining the existing Snapshots. To convert volumes successfully:
There must be a common Snapshot copy of the volumes.
You must break the existing SnapMirror relationship, add the volumes to a single consistency group, then resynchronize the relationship using the following workflow.

Steps

From the destination cluster, select Storage > Consistency groups.
Select the consistency group you have created from the Consistency group menu.
At the top right of the overview page, select More then Protect.
ONTAP System Manager auto-fills source-side information. Select the appropriate cluster and storage VM for the destination. Select a protection policy. Ensure that Initialize relationship is checked.

When selecting an asynchronous policy, you have the option to Override Transfer Schedule.

The minimum supported schedule (recovery point objective, or RPO) for consistency groups with asynchronous SnapMirror is 30 minutes.
Select Save.
The consistency group needs to initialize and synchronize. Confirm synchronization has completed successfully by returning to the Consistency group menu. The SnapMirror (Remote) status displays Protected next to .

Visualize relationships

ONTAP System Manager visualizes LUN maps under the Protection > Relationships menu. When you select a source relationship, ONTAP System Manager displays a visualization of the source relationships. By selecting a volume, you can delve deeper into these relationships to see a list of the contained LUNs and the initiator group relationships. This information can be downloaded as an Excel workbook from the individual volume view; the download operation will run in the background.

Related information