Prepare Clusters

Prepare participating clusters

Before you prepare your clusters to participate in an Active-Active database, make sure you've completed all the following steps and have gathered the information listed below each step.

1. Configure the [admission controller and ValidatingWebhook]({{< relref "/operate/kubernetes/deployment/quick-start#enable-the-admission-controller/" >}}).

2. Create two or more [RedisEnterpriseCluster (REC) custom resources]({{< relref "/operate/kubernetes/deployment/quick-start#create-a-redis-enterprise-cluster-rec" >}}) with enough [memory resources]({{< relref "/operate/rs/installing-upgrading/install/plan-deployment/hardware-requirements" >}}).

   • Name of each REC (<rec-name>)
   • Namespace for each REC (<rec-namespace>)

3. Configure the REC [ingressOrRoutes field]({{< relref "/operate/kubernetes/networking/ingressorroutespec" >}}) and [create DNS records]({{< relref "/operate/kubernetes/networking/ingressorroutespec#configure-dns/" >}}).

   • REC API hostname (api-<rec-name>-<rec-namespace>.<subdomain>)
   • Database hostname suffix (-db-<rec-name>-<rec-namespace>.<subdomain>)

Next you'll collect credentials for your participating clusters and create secrets for the RedisEnterprsieRemoteCluster (RERC) to use.

For a list of example values used throughout this article, see the Example values section.

Collect REC credentials

To communicate with other clusters, all participating clusters will need access to the admin credentials for all other clusters.

1. Create a file to hold the admin credentials for all participating RECs (such as all-rec-secrets.yaml).

2. Within that file, create a new secret for each participating cluster named redis-enterprise-<rerc-name>.

   The example below shows a file (all-rec-secrets.yaml) holding secrets for two participating clusters:

   yamlCopy

   apiVersion: v1
   data:
     password: 
     username: 
   kind: Secret
   metadata:
     name: redis-enterprise-rerc-ohare
   type: Opaque
   
   ---
   
   apiVersion: v1
   data:
     password: 
     username: 
   kind: Secret
   metadata:
     name: redis-enterprise-rerc-reagan
   type: Opaque
   
   

3. Get the REC credentials secret for each participating cluster.

   shCopy

   kubectl get secret -o yaml <rec-name>
   

   The admin credentials secret for an REC named rec-chicago would be similar to this:

   yamlCopy

   apiVersion: v1
   data:
     password: ABcdef12345
     username: GHij56789
   kind: Secret
   metadata:
     name: rec-chicago
   type: Opaque
   

   {{< note >}} The username and password values should be base64 encoded, not plain text. {{< /note >}}

4. Add the username and password to the new secret for that REC and namespace.

   This example shows the collected secrets file (all-rec-secrets.yaml) for rerc-ohare (representing rec-chicago in namespace ns-illinois) and rerc-reagan (representing rec-arlington in namespace ns-virginia).

   yamlCopy

   apiVersion: v1
   data:
     password: ABcdef12345
     username: GHij56789
   kind: Secret
   metadata:
     name: redis-enterprise-rerc-ohare
   type: Opaque
   
   ---
   
   apiVersion: v1
   data:
     password: KLmndo123456
     username: PQrst789010
   kind: Secret
   metadata:
     name: redis-enterprise-rerc-reagan
   type: Opaque
   
   

5. Apply the file of collected secrets to every participating REC.

   shCopy

   kubectl apply -f <all-rec-secrets-file>
   

   If the admin credentials for any of the clusters changes, the file will need to be updated and reapplied to all clusters.

Next steps

Now you are ready to [create your Redis Enterprise Active-Active database]({{< relref "/operate/kubernetes/active-active/create-reaadb" >}}).

Example values

This article uses the example values listed below. They can also be found in the [YAML examples]({{< relref "/operate/kubernetes/reference/yaml/active-active" >}}) section.

Example cluster 1:

• REC name: rec-chicago
• REC namespace: ns-illinois
• RERC name: rerc-ohare
• RERC secret name: redis-enterprise-rerc-ohare
• API FQDN: api-rec-chicago-ns-illinois.example.com
• DB FQDN suffix: -db-rec-chicago-ns-illinois.example.com

Example cluster 2:

• REC name: rec-arlington
• REC namespace: ns-virginia
• RERC name: rerc-raegan
• RERC secret name: redis-enterprise-rerc-reagan
• API FQDN: api-rec-arlington-ns-virginia.example.com
• DB FQDN suffix: -db-rec-arlington-ns-virginia.example.com