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Redis Enterprise [Active-Active]({{< relref "/operate/rs/databases/active-active/" >}}) databases on Kubernetes provide read and write access to the same dataset from different Kubernetes clusters. This enables globally distributed applications with local read and write access, automatic conflict resolution, and seamless failover capabilities.

Active-Active databases use multi-master replication to keep data synchronized across participating clusters, allowing applications to read and write data locally while maintaining global consistency.

Active-Active setup methods

There are two methods for creating an Active-Active database with Redis Enterprise for Kubernetes:

  • The RedisEnterpriseActiveActiveDatabase (REAADB) custom resource is available for versions 6.4.2 and later.
  • The crdb-cli method is available for versions 6.4.2 or earlier.

We recommend creating new Active-Active databases using the RedisEnterpriseActiveActiveDatabase (REAADB) custom resource. This allows you to manage your Active-Active database with the operator and ensures you have the latest features and functionality.

Active-Active controller method

Versions 6.4.2-6 or later fully support the Active-Active controller. Some of these features were available as a preview in 6.4.2-4 and 6.4.2-5. Please upgrade to 6.4.2-6 for the full set of general availability features and bug fixes.

This setup method includes the following steps:

  1. Gather REC credentials and [prepare participating clusters]({{< relref "/operate/kubernetes/active-active/prepare-clusters" >}}).
  2. Create [RedisEnterpriseRemoteCluster (RERC)]({{< relref "/operate/kubernetes/active-active/create-reaadb#create-rerc" >}}) resources.
  3. Create [RedisEnterpriseActiveActiveDatabase (REAADB)]({{< relref "/operate/kubernetes/active-active/create-reaadb#create-reaadb" >}}) resource.

crdb-cli method

For versions 6.4.2 or earlier, this Active-Active setup method includes the following steps:

  1. Install and configure an ingress.
  2. Gather configuration details.
  3. Add the ActiveActive field to the REC spec.
  4. Create the database with the crdb-cli tool.

Redis Enterprise Active-Active controller for Kubernetes

{{<note>}}These features are supported for general availability in releases 6.4.2-6 and later.{{</note>}}

[Active-Active]({{< relref "/operate/rs/databases/active-active/" >}}) databases give you read-and-write access to Redis Enterprise clusters (REC) in different Kubernetes clusters or namespaces. Active-Active deployments managed by the Redis Enterprise operator require two additional custom resources: Redis Enterprise Active-Active database (REAADB) and Redis Enterprise remote cluster (RERC).

To create an Active-Active Redis Enterprise deployment for Kubernetes with these new features, first [prepare participating clusters]({{< relref "/operate/kubernetes/active-active/prepare-clusters" >}}) then [create an Active-Active database]({{< relref "/operate/kubernetes/active-active/create-reaadb" >}}).

REAADB custom resource

Redis Enterprise Active-Active database (REAADB) contains a link to the RERC for each participating cluster, and provides configuration and status to the management plane.

For a full list of fields and options, see the [REAADB API reference]({{<relref "/operate/kubernetes/reference/api/redis_enterprise_active_active_database_api">}}).

For examples, see the [YAML examples]({{< relref "/operate/kubernetes/reference/yaml/active-active" >}}) section.

RERC custom resource

Redis Enterprise remote cluster (RERC) custom resource contains configuration details for all the participating clusters.

For a full list of fields and options, see the [RERC API reference]({{<relref "/operate/kubernetes/reference/api/redis_enterprise_remote_cluster_api">}}).

For examples, see the [YAML examples]({{< relref "/operate/kubernetes/reference/yaml/active-active" >}}) section.

Limitations

  • Existing Redis databases cannot be migrated to a REAADB. (DOC-3594)
  • Admission is not blocking REAADB with shardCount which exceeds license quota. (RED-96301) Workaround: Fix the problems with the REAADB and reapply.
  • The <rec-name>/<rec-namespace> value must be unique for each RERC resource. (RED-96302)
  • Only global database options are supported, no support for specifying configuration per location.
  • No support for migration from old (crdb-cli) Active-Active database method to new Active-Active controller.
  • No support for REAADB with participating clusters co-located within the same Kubernetes cluster, except for a single designated local participating cluster.
  • Active-Active databases cannot be configured as [Redis Flex]({{< relref "/operate/kubernetes/re-clusters/redis-flex" >}}) deployments.

More info

For more general information about Active-Active, see the [Redis Enterprise Software docs]({{< relref "/operate/rs/databases/active-active/" >}}).