# Create Active-Active databases with crdb-cli ```json metadata { "schema_version": 2, "title": "Create Active-Active databases with crdb-cli", "description": "This section shows how to set up an Active-Active Redis Enterprise database on Kubernetes using the Redis Enterprise Software operator.", "categories": ["docs","operate","kubernetes"], "tableOfContents": {"sections":[{"id":"prerequisites","title":"Prerequisites"},{"id":"document-required-parameters","title":"Document required parameters"},{"children":[{"id":"using-ingress-controller","title":"Using ingress controller"},{"id":"using-openshift-routes","title":"Using OpenShift routes"}],"id":"add-activeactive-section-to-the-rec-resource-file","title":"Add activeActive section to the REC resource file"},{"id":"create-an-active-active-database-with-crdb-cli","title":"Create an Active-Active database with crdb-cli"},{"id":"test-your-database","title":"Test your database"}]} , "codeExamples": [] } ``` > [!NOTE] > Versions 6.4.2 and later support the Active-Active database controller. This controller allows you to create Redis Enterprise Active-Active databases (REAADB) and Redis Enterprise remote clusters (RERC) with custom resources. We recommend using the [REAADB method for creating Active-Active databases](https://redis.io/docs/latest/operate/kubernetes/active-active/create-reaadb). On Kubernetes, Redis Enterprise [Active-Active](https://redis.io/docs/latest/operate/rs/databases/active-active) databases provide read-and-write access to the same dataset from different Kubernetes clusters. For more general information about Active-Active, see the [Redis Enterprise Software docs](https://redis.io/docs/latest/operate/rs/databases/active-active). Creating an Active-Active database requires routing [network access](https://redis.io/docs/latest/operate/kubernetes/networking) between two Redis Enterprise clusters residing in different Kubernetes clusters. Without the proper access configured for each cluster, syncing between the databases instances will fail. This process consists of: 1. Documenting values to be used in later steps. It's important these values are correct and consistent. 1. Editing the Redis Enterprise cluster (REC) spec file to include the `ActiveActive` section. This will be slightly different depending on the K8s distribution you are using. 1. Creating the database with the `crdb-cli` command. These values must match up with values in the REC resource spec. ## Prerequisites Before creating Active-Active databases, you'll need admin access to two or more working Kubernetes clusters that each have: - Routing for external access with an [ingress resources](https://redis.io/docs/latest/operate/kubernetes/networking/ingress) (or [route resources](https://redis.io/docs/latest/operate/kubernetes/networking/routes) on OpenShift). - A working [Redis Enterprise cluster (REC)](https://redis.io/docs/latest/operate/kubernetes/reference/api/redis_enterprise_cluster_api) with a unique name. - Enough memory resources available for the database (see [hardware requirements](https://redis.io/docs/latest/operate/rs/installing-upgrading/install/plan-deployment/hardware-requirements)). > [!NOTE] > The `activeActive` field and the `ingressOrRouteSpec` field cannot coexist in the same REC. If you configured your ingress via the `ingressOrRouteSpec` field in the REC, create your Active-Active database with the RedisEnterpriseActiveActiveDatabase (REAADB) custom resource. ## Document required parameters The most common mistake when setting up Active-Active databases is incorrect or inconsistent parameter values. The values listed in the resource file must match those used in the crdb-cli command. - **Database name** ``: - Description: Combined with ingress suffix to create the Active-Active database hostname - Format: string - Example value: `myaadb` - How you get it: you choose - The database name requirements are: - Maximum of 63 characters - Only letter, number, or hyphen (-) characters - Starts with a letter; ends with a letter or digit. - Database name is not case-sensitive You'll need the following information for each participating Redis Enterprise cluster (REC): > [!NOTE] > You'll need to create DNS aliases to resolve your API hostname ``,``, `` to the IP address for the ingress controller’s LoadBalancer (or routes in Openshift) for each database. To avoid entering multiple DNS records, you can use a wildcard in your alias (such as *.ijk.example.com). - **REC hostname** ``: - Description: Hostname used to identify your Redis Enterprise cluster in the `crdb-cli` command. This MUST be different from other participating clusters. - Format: `..svc.cluster.local` - Example value: `rec01.ns01.svc.cluster.local` - How to get it: List all your Redis Enterprise clusters ```bash kubectl get rec ``` - **API hostname** ``: - Description: Hostname used to access the Redis Enterprise cluster API from outside the K8s cluster - Format: string - Example value: `api.ijk.example.com` - **Ingress suffix** ``: - Description: Combined with database name to create the Active-Active database hostname - Format: string - Example value: `-cluster.ijk.example.com` - [**REC admin credentials**](https://redis.io/docs/latest/operate/kubernetes/security/authentication/manage-rec-credentials) ` `: - Description: Admin username and password for the REC stored in a secret - Format: string - Example value: username: `user@example.com`, password: `something` - How to get them: ```sh kubectl get secret \ -o jsonpath='{.data.username}' | base64 --decode kubectl get secret \ -o jsonpath='{.data.password}' | base64 --decode ``` - **Replication hostname** ``: - Description: Hostname used inside the ingress for the database - Format: `` - Example value: `myaadb-cluster.ijk.example.com` - How to get it: Combine `` and ` values you documented above. - **Replication endpoint** ``: - Description: Endpoint used externally to contact the database - Format: `:443` - Example value: `myaadb-cluster.ijk.example.com:443` - How to get it:`:443` ## Add `activeActive` section to the REC resource file From inside your K8s cluster, edit your Redis Enterprise cluster (REC) resource to add the following to the `spec` section. Do this for each participating cluster. The operator uses the API hostname (``) to create an ingress to the Redis Enterprise cluster's API; this only happens once per cluster. Every time a new Active-Active database instance is created on this cluster, the operator creates a new ingress route to the database with the ingress suffix (``). The hostname for each new database will be in the format ``. ### Using ingress controller 1. If your cluster uses an [ingress controller](https://redis.io/docs/latest/operate/kubernetes/networking/ingress), add the following to the `spec` section of your REC resource file. Nginx: ```sh activeActive: apiIngressUrl: dbIngressSuffix: ingressAnnotations: kubernetes.io/ingress.class: nginx nginx.ingress.kubernetes.io/backend-protocol: HTTPS nginx.ingress.kubernetes.io/ssl-passthrough: "true" method: ingress ``` HAproxy: ```sh activeActive: apiIngressUrl: dbIngressSuffix: ingressAnnotations: kubernetes.io/ingress.class: haproxy ingress.kubernetes.io/ssl-passthrough: "true" method: ingress ``` 2. After the changes are saved and applied, you can verify a new ingress was created for the API. ```sh $ kubectl get ingress NAME HOSTS ADDRESS PORTS AGE rec01 api.abc.cde.example.com 225161f845b278-111450635.us.cloud.com 80 24h ``` 3. Verify you can access the API from outside the K8s cluster. ```sh curl -k -L -i -u : https:///v1/cluster ``` If the API call fails, create a DNS alias that resolves your API hostname (``) to the IP address for the ingress controller's LoadBalancer. 4. Make sure you have DNS aliases for each database that resolve your API hostname ``,``, `` to the IP address of the ingress controller’s LoadBalancer. To avoid entering multiple DNS records, you can use a wildcard in your alias (such as `*.ijk.example.com`). #### If using Istio Gateway and VirtualService No changes are required to the REC spec if you are using [Istio](https://redis.io/docs/latest/operate/kubernetes/networking/istio-ingress) in place of an ingress controller. The `activeActive` section added above creates ingress resources. The two custom resources used to configure Istio (Gateway and VirtualService) replace the need for ingress resources. > [!WARNING] > These custom resources are not controlled by the operator and will need to be configured and maintained manually. For each cluster, verify the VirtualService resource has two `- match:` blocks in the `tls` section. The hostname under `sniHosts:` should match your ``. ### Using OpenShift routes 1. Make sure your Redis Enterprise cluster (REC) has a different name (``) than any other participating clusters. If not, you'll need to manually rename the REC or move it to a different namespace. You can check your new REC name with: ```sh oc get rec -o jsonpath='{.items[0].metadata.name}' ``` If the rec name was modified, reapply [scc.yaml](https://github.com/RedisLabs/redis-enterprise-k8s-docs/blob/master/openshift/scc.yaml) to the namespace to reestablish security privileges. ```sh oc apply -f scc.yaml oc adm policy add-scc-to-group redis-enterprise-scc-v2 system:serviceaccounts: ``` Releases before 6.4.2-6 use the earlier version of the SCC, named `redis-enterprise-scc`. 1. Make sure you have DNS aliases for each database that resolve your API hostname ``,``, `` to the route IP address. To avoid entering multiple DNS records, you can use a wildcard in your alias (such as `*.ijk.example.com`). 1. If your cluster uses [OpenShift routes](https://redis.io/docs/latest/operate/kubernetes/networking/routes), add the following to the `spec` section of your Redis Enterprise cluster (REC) resource file. ```sh activeActive: apiIngressUrl: dbIngressSuffix: method: openShiftRoute ``` 1. Make sure you have DNS aliases that resolve to the routes IP for both the API hostname (``) and the replication hostname (``) for each database. To avoid entering each database individually, you can use a wildcard in your alias (such as `*.ijk.example.com`). 1. After the changes are saved and applied, you can see that a new route was created for the API. ```sh $ oc get route NAME HOST/PORT PATH SERVICES PORT TERMINATION WILDCARD rec01 api-openshift.apps.abc.example.com rec01 api passthrough None ``` ## Create an Active-Active database with `crdb-cli` The `crdb-cli` command can be run from any Redis Enterprise pod hosted on any participating K8s cluster. You'll need the values for the [required parameters](https://redis.io/docs/latest/operate/kubernetes/active-active/create-aa-crdb-cli#document-required-parameters) for each Redis Enterprise cluster. ```sh crdb-cli crdb create \ --name \ --memory-size \ --encryption yes \ --instance fqdn=,url=https://,username=,password=,replication_endpoint=,replication_tls_sni= \ --instance fqdn=,url=https://,username=,password=,replication_endpoint=,replication_tls_sni= ``` To create a database that syncs between more than two instances, add additional `--instance` arguments. See the [`crdb-cli` reference](https://redis.io/docs/latest/operate/rs/references/cli-utilities/crdb-cli) for more options. ## Test your database The easiest way to test your Active-Active database is to set a key-value pair in one database and retrieve it from the other. You can connect to your databases with the instructions in [Manage databases](https://redis.io/docs/latest/operate/kubernetes/re-databases/db-controller#connect-to-a-database). Set a test key with `SET foo bar` in the first database. If your Active-Active deployment is working properly, when connected to your second database, `GET foo` should output `bar`.