kubernetesdiscourse

Scale the cluster horizontally

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By default, this Chart only deploys a single pod running Discourse. Should you want to increase the number of replicas, you may follow these simple steps to ensure everything works smoothly:

TIP: Running these steps ensures the PostgreSQL instance is correctly populated. If you already have an initialised database, you may directly create a release with the desired number of replicas. Remind to set discourse.skipInstall to true.

  • Create a conventional release, that will be scaled later:

      $ helm install MY-RELEASE bitnami/discourse

  • Wait for the release to complete and execute the following:

      $ export DISCOURSE_PASSWORD=$(kubectl get secret --namespace default MY-RELEASE-discourse -o jsonpath="{.data.discourse-password}" | base64 --decode)
  $ export POSTGRESQL_PASSWORD=$(kubectl get secret --namespace default MY-RELEASE-postgresql -o jsonpath="{.data.postgresql-password}" | base64 --decode)

  • Check the pods to confirm that the chart was successfully deployed:

      $ kubectl get pods
  NAME                               READY   STATUS    RESTARTS   AGE
  MY-RELEASE-discourse-744c48dd97-wx5h9   2/2     Running   0          5m11s
  MY-RELEASE-postgresql-0                 1/1     Running   0          5m10s
  MY-RELEASE-redis-master-0               1/1     Running   0          5m11s

  • Perform an upgrade specifying the number of replicas and the credentials used.

      $ helm upgrade MY-RELEASE --set replicaCount=2,discourse.password=$DISCOURSE_PASSWORD,postgresql.postgresqlPassword=$POSTGRESQL_PASSWORD,discourse.skipInstall=true bitnami/discourse

NOTE: You need to provide ReadWriteMany PVCs. If you don’t have a provisioner for this type of storage, we recommend that you install the NFS provisioner chart (with the correct parameters, such as persistence.enabled=true and persistence.size=10Gi) and map it to a RWO volume. Then, deploy the Discourse chart using the proper parameters:

persistence.storageClass=nfs postgresql.persistence.storageClass=nfs