How to enable replication

You can enable High Availability features for a new or existing Namespace by adding a replica. When you add a replica, Temporal Cloud begins the replication of ongoing and existing Workflow Executions. Once the replication is complete and the replica is ready, your Namespace is ready for failover.

Advantages of using Temporal Cloud’s High Availability features:

• No manual deployment or configuration needed, just simple push-button operations.
• Existing Workflows resume seamlessly in the replica with minimal interruption and data loss.
• No changes needed for Worker and Workflow code during setup or failover.
• 99.99% contractual SLA.

High Availability features

Support, stability, and dependency info

Same-region Replication is in Public Preview for Temporal Cloud.

Temporal offers the following High Availability features, which you can configure at a Namespace level.

• Same-region Replication: Workflows are seamlessly replicated to a different isolation domain within the same region as the primary. This option is a good fit if your application is architected to be in one region and you would prefer to failover within the same region. It provides a reliable failover mechanism while maintaining deployment simplicity. GCP Namespaces do not support Same-region Replication.
• Multi-region Replication: Workflows are seamlessly replicated to a different region that you choose. Replicating Workflows across different regions enhances resilience and reliability. This is particularly beneficial for organizations with multi-regional architectures or those required to be highly available across regions for compliance purposes. This option is a good fit if your application is architected to be multi-region. GCP Namespaces support Multi-region Replication.

There are charges associated with Replication and enabling High Availability features. For pricing details, visit Temporal Cloud's Pricing page. This page explains how to enable and manage these features.

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. The following table explains how:

Approach	Instructions
Web UI	Visit Temporal Cloud in your Web browser. During Namespace creation, specify the primary region for the Namespace. Select "Add a replica": Adding a replica in the same region enables Same-region Replication. Adding a replica in a different region (within the same continent) replicates across regions for Multi-region Replication. You cannot create a Multi-region deployment on separate continents. 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 once your Namespace is ready for use.
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. Using the same region replicates to an isolation domain within that region. Using a different region (within the same continent) replicates across regions. You cannot create a Multi-region deployment on separate continents. If using API key authentication with the --api-key flag, you must add it directly after the tcld command and before namespace create.

caution

Same-region Replication is not supported in all regions. For Multi-region Replication, pairing is limited to regions within the same continent. Contact Support to request more regions.

Upgrade an existing Namespace with High Availability functionality

Upgrade an existing standard Namespace by adding High Availability features. Adding a replica unlocks that functionality.

The following table explains how:

Approach	Instructions
Web UI	Visit Temporal Cloud Namespaces in your Web browser. Navigate to the Namespace details page. Select the “Add a replica” button. Choose either Same-region Replication or Multi-region Replication (across regions). If you select Multi-region Replication, specify which region. You cannot create a Multi-region deployment on separate continents. 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 once your Namespace 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 code of the region where you want to create the replica as an argument to the --region flag. Using the current region replicates to an isolation domain within your existing region. Using a different region (within the same continent) replicates across regions (Multi-region Replication). You cannot create a Multi-region deployment on separate continents. 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

caution

We discourage changing the location of your replica for deployed applications, except under exceptional circumstances. Changing the location of your Namespace replica will result in a mandatory 7-day waiting period before you can re-enable High Availability Namespace features.

Temporal Cloud can't change replica locations directly. To update the location, you need to remove the current replica and add a new one. Follow these steps to change the replica location:

1. Remove your replica. This disables High Availability for your Namespace.
2. Wait through the required 7-day waiting period.
3. Add a new replica to your Namespace.

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

Discontinue High Availability features

Removing a Namespace replica disables High Availability and automatic failover features. Follow these steps to disable these features and end High Availability charges:

Approach	Instructions
Web UI	Navigate to the Namespace details page in Temporal Cloud Select the option to "Remove Replica" on the "Region" card.
tcld	At the command line, enter: tcld namespace delete-region \ --namespace <namespace_id>.<account_id> \ --region <replica_region> If using API key authentication with the --api-key flag, you must add it directly after the tcld command and before namespace delete-region

After following these instructions, Temporal Cloud deletes the replica. Your Namespace will no longer use High Availability features and you will no longer be charged for this feature.

note

After removing a replica, Temporal Cloud can't re-enable replication for a given Namespace for seven days.