Enable High Availability

You can enable High Availability features for a new or existing Namespace by adding a replica. When you add a replica, Temporal Cloud begins asynchronously replicating ongoing and existing Workflow Executions.

The replica region must be on the same continent as the primary region. Because of that, not all replication options are available in all Temporal Cloud regions. See the Service regions page for the supported replica regions for each active region.

Using private network connectivity with a HA namespace requires extra setup. See Connectivity for HA.

There are charges associated with Replication and enabling High Availability features. For pricing details, visit Temporal Cloud's Pricing page.

Create a Namespace with High Availability features

To create a new Namespace with High Availability features, you can use the Temporal Cloud UI or the tcld command line utility.

Web UI

1. Visit Temporal Cloud in your Web browser.
2. During Namespace creation, specify the primary region for the Namespace.
3. Select "Add a replica".
4. Choose the region for the replica.

The web interface will present an estimated time for replication to complete. This time is based on your selection and the size and scale of the Workflows in your Namespace.

tcld

At the command line, enter:

tcld namespace create \
   --namespace <namespace_id>.<account_id> \
   --region <primary_region> \
   --region <replica_region>

Specify the region codes as arguments to the two --region flags.

If using API key authentication with the --api-key flag, you must add it directly after the tcld command and before namespace create.

Temporal Cloud sends an email alert to all Namespace Admins once your Namespace replica is ready for use.

Add High Availability to an existing Namespace

A replica can be added after a namespace has already been created.

Web UI

1. Visit Temporal Cloud Namespaces in your Web browser.
2. Navigate to the Namespace details page.
3. Select the “Add a replica” button.
4. Choose the region for the replica.

The web interface will present an estimated time for replication to complete. This time is based on your selection and the size and scale of the Workflows in your Namespace.

Temporal Cloud sends an email alert to all Namespace Admins once your Namespace replica is ready for use.

tcld

At the command line, enter:

tcld namespace add-region \
   --namespace <namespace_id>.<account_id> \
   --region <replica_region>

Specify the region name (for example, us-east-1) of the region where you want to create the replica as an argument to the --region flag. See Regions for available region names.

If using API key authentication with the --api-key flag, you must add it directly after the tcld command and before namespace add-region.

Temporal Cloud sends an email alert once your Namespace is ready for use.

Change a replica location

Temporal Cloud can't change replica locations directly. To change a replica's location, you need to remove the replica and add a new one.

caution

We discourage changing the location of your replica for deployed applications, except under exceptional circumstances. If you remove your replica, you lose the availability guarantees of the Namespace, and it can take time to add another replica.

If you remove a replica from a region, you must wait seven days before you can re-enable High Availability (HA) in that same location. During this period, you may add a replica to a different region, provided you have not had one there within the last seven days.

Follow these steps to change the replica location:

1. Remove your replica. This disables High Availability for your Namespace.
2. Add a new replica to your Namespace.

You will receive an email alert once your Namespace is ready for use.

Disable High Availability (remove a replica)

To disable High Availability features on a Namespace, remove the replica from that Namespace. Removing a replica disables all High Availability features:

• Discontinues replication of the Workflows in the Namespace.
• Disables the Namespace's ability to trigger a failover to a different region or cloud.
• Ends High Availability charges.

caution

After removing a Namespace's replica, you cannot add a new replica to that same region for seven days. During that time, you can still add a replica to any other region.

Follow these steps to remove a replica from a Namespace:

Web UI

1. Navigate to the Namespace details page in Temporal Cloud
2. Select the option to "Remove Replica" on the "Region" card.

tcld

Run the following command to remove the replica:

tcld namespace delete-region \
    --api-key <api_key> \
    --namespace <namespace_id>.<account_id> \
    --region <replica_region_name>

See Regions for available region names.