Upgrade Method #1: Data Volumes
This upgrade method allows you to migrate from PGO v4 to PGO v5 using the existing data volumes that were created in PGO v4. Note that this is an “in place” migration method: this will immediately move your Postgres clusters from being managed by PGO v4 and PGO v5. If you wish to have some failsafes in place, please use one of the other migration methods. Please also note that you will need to perform the cluster upgrade in the same namespace as the original cluster in order for your v5 cluster to access the existing PVCs.
Step 1: Prepare the PGO v4 Cluster for Migration
You will need to set up your PGO v4 Postgres cluster so that it can be migrated to a PGO v5 cluster. The following describes how to set up a PGO v4 cluster for using this migration method.
- Scale down any existing replicas within the cluster. This will ensure that the primary PVC does not change again prior to the upgrade.
You can get a list of replicas using the
pgo scaledown --query command, e.g.:
pgo scaledown hippo --query
If there are any replicas, you will see something similar to:
Cluster: hippo REPLICA STATUS NODE ... hippo running node01 ...
Scaledown any replicas that are running in this cluser, e.g.:
pgo scaledown hippo --target=hippo
2. Once all replicas are removed and only the primary remains, proceed with deleting the cluster while retaining the data and backups. You can do this
You MUST run this command with the
--keep-backups flag otherwise you risk deleting ALL of your data.
pgo delete cluster hippo --keep-data --keep-backups
3. The PVC for the primary Postgres instance and the pgBackRest repository should still remain. You can verify this with the command below:
kubectl get pvc --selector=pg-cluster=hippo
This should yield something similar to:
NAME STATUS VOLUME ... hippo-jgut Bound pvc-a0b89bdb- ... hippo-pgbr-repo Bound pvc-25501671- …
A third PVC used to store write-ahead logs (WAL) may also be present if external WAL volumes were enabled for the cluster.
Step 2: Migrate to PGO v5
With the PGO v4 cluster’s volumes prepared for the move to PGO v5, you can now create a
PostgresCluster custom resource using these volumes. This migration method does not carry over any specific configurations or customizations from PGO v4: you will need to create the specific
PostgresCluster configuration that you need.
26to match the
postgresgroup used in PGO v5. Please see here for more information.
To complete the upgrade process, your
PostgresCluster custom resource MUST include the following:
volumes data source that points to the PostgreSQL data, PostgreSQL WAL (if applicable) and pgBackRest repository PVCs identified in the
For example, using the
spec: dataSource: volumes: pgDataVolume: pvcName: hippo-jgut directory: "hippo-jgut" pgBackRestVolume: pvcName: hippo-pgbr-repo directory: "hippo-backrest-shared-repo" # Only specify external WAL PVC if enabled in PGO v4 cluster. If enabled # in v4, a WAL volume must be defined for the v5 cluster as well. # pgWALVolume: # pvcName: hippo-jgut-wal
To avoid that behavior, follow the instructions in the section on removing PGO v4 labels.
2. If you customized Postgres parameters, you will need to ensure they match in the PGO v5 cluster. For more information, please review the tutorial on customizing a Postgres cluster.
3. Once the
PostgresCluster spec is populated according to these guidelines, you can create the
PostgresCluster custom resource. For example, if the
PostgresCluster you’re creating is a modified version of the
postgres example in the PGO examples repo, you can run the following command:
kubectl apply -k examples/postgrescluster
Your upgrade is now complete! You should now remove the
spec.dataSource.volumes section from your
PostgresCluster. For more information on how to use PGO v5, we recommend reading through the PGO v5 tutorial.