bitnamicharts/postgresql repository overview

⁠Bitnami Secure Images Helm chart for PostgreSQL

PostgreSQL (Postgres) is an open source object-relational database known for reliability and data integrity. ACID-compliant, it supports foreign keys, joins, views, triggers and stored procedures.

Overview of PostgreSQL⁠

Trademarks: This software listing is packaged by Bitnami. The respective trademarks mentioned in the offering are owned by the respective companies, and use of them does not imply any affiliation or endorsement.

⁠ TL;DR

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/postgresql

⁠ Introduction

This chart bootstraps a PostgreSQL⁠ deployment on a Kubernetes⁠ cluster using the Helm⁠ package manager.

For HA, please see this repo⁠

⁠ Before you begin

• Kubernetes 1.23+
• Helm 3.8.0+
• PV provisioner support in the underlying infrastructure

⁠ Installing the Chart

To install the chart with the release name my-release:

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/postgresql

The command deploys PostgreSQL on the Kubernetes cluster in the default configuration. The Parameters⁠ section lists the parameters that can be configured during installation.

⁠ Configuration and installation details

This section describes credentials, configuration, and other installation options.

⁠ Resource requests and limits

Bitnami charts allow setting resource requests and limits for all containers inside the chart deployment. These are inside the resources value (check parameter table). Setting requests is essential for production workloads and these should be adapted to your specific use case.

To make this process easier, the chart contains the resourcesPreset values, which automatically sets the resources section according to different presets. Check these presets in the bitnami/common chart⁠. However, in production workloads using resourcesPreset is discouraged as it may not fully adapt to your specific needs. Find more information on container resource management in the official Kubernetes documentation⁠.

⁠ Prometheus metrics

This chart can be integrated with Prometheus by setting metrics.enabled to true. This will deploy a sidecar container with postgres_exporter⁠ in all pods. It will also create metrics services that can be configured under the metrics.service section. These services will be have the necessary annotations to be automatically scraped by Prometheus.

⁠Prometheus requirements

It is necessary to have a working installation of Prometheus or Prometheus Operator for the integration to work. Install the Bitnami Prometheus helm chart⁠ or the Bitnami Kube Prometheus helm chart⁠ to easily have a working Prometheus in your cluster.

⁠Integration with Prometheus Operator

The chart can deploy ServiceMonitor objects for integration with Prometheus Operator installations. To do so, set the value metrics.serviceMonitor.enabled=true. Ensure that the Prometheus Operator CustomResourceDefinitions are installed in the cluster or it will fail with the following error:

no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"

Install the Bitnami Kube Prometheus helm chart⁠ for having the necessary CRDs and the Prometheus Operator.

⁠ Rolling VS Immutable tags⁠

It is strongly recommended to use immutable tags in a production environment. This ensures your deployment does not change automatically if the same tag is updated with a different image.

Bitnami will release a new chart updating its containers if a new version of the main container, significant changes, or critical vulnerabilities exist.

⁠ Customizing primary and read replica services in a replicated configuration

At the top level, there is a service object which defines the services for both primary and readReplicas. For deeper customization, there are service objects for both the primary and read types individually. This allows you to override the values in the top level service object so that the primary and read can be of different service types and with different clusterIPs / nodePorts. Also in the case you want the primary and read to be of type nodePort, you will need to set the nodePorts to different values to prevent a collision. The values that are deeper in the primary.service or readReplicas.service objects will take precedence over the top level service object.

⁠ Use a different PostgreSQL version

To modify the application version used in this chart, specify a different version of the image using the image.tag parameter and/or a different repository using the image.repository parameter.

⁠ LDAP

LDAP support can be enabled in the chart by specifying the ldap. parameters while creating a release. The following parameters should be configured to properly enable the LDAP support in the chart.

• ldap.enabled: Enable LDAP support. Defaults to false.
• ldap.uri: LDAP URL beginning in the form ldap[s]://<hostname>:<port>. No defaults.
• ldap.base: LDAP base DN. No defaults.
• ldap.binddn: LDAP bind DN. No defaults.
• ldap.bindpw: LDAP bind password. No defaults.
• ldap.bslookup: LDAP base lookup. No defaults.
• ldap.nss_initgroups_ignoreusers: LDAP ignored users. root,nslcd.
• ldap.scope: LDAP search scope. No defaults.
• ldap.tls_reqcert: LDAP TLS check on server certificates. No defaults.

For example:

ldap.enabled="true"
ldap.uri="ldap://my_ldap_server"
ldap.base="dc=example\,dc=org"
ldap.binddn="cn=admin\,dc=example\,dc=org"
ldap.bindpw="admin"
ldap.bslookup="ou=group-ok\,dc=example\,dc=org"
ldap.nss_initgroups_ignoreusers="root\,nslcd"
ldap.scope="sub"
ldap.tls_reqcert="demand"

Next, login to the PostgreSQL server using the psql client and add the PAM authenticated LDAP users.

⁠ Update credentials

Bitnami charts, with its default settings, configure credentials at first boot. Any further change in the secrets or credentials can be done using one of the following methods:

⁠ Manual update of the passwords and secrets

• Update the user password following the upstream documentation⁠
• Update the password secret with the new values (replace the SECRET_NAME, PASSWORD and POSTGRES_PASSWORD placeholders)

kubectl create secret generic SECRET_NAME --from-literal=password=PASSWORD --from-literal=postgres-password=POSTGRES_PASSWORD --dry-run -o yaml | kubectl apply -f -

⁠ Automated update using a password update job

The Bitnami PostgreSQL provides a password update job that will automatically change the PostgreSQL passwords when running helm upgrade. To enable the job set passwordUpdateJob.enabled=true. This job requires:

• The new passwords: this is configured using either auth.postgresPassword, auth.password and auth.replicationPassword (if applicable) or setting auth.existingSecret.
• The previous passwords: This value is taken automatically from already deployed secret object. If you are using auth.existingSecret or helm template instead of helm upgrade, then set either passwordUpdateJob.previousPasswords.postgresPassword, passwordUpdateJob.previousPasswords.password, passwordUpdateJob.previousPasswords.replicationPassword (when applicable), or setting passwordUpdateJob.previousPasswords.existingSecret.

In the following example we update the password via values.yaml in a PostgreSQL installation with replication

architecture: "replication"

auth:
  user: "user"
  postgresPassword: "newPostgresPassword123"
  password: "newUserPassword123"
  replicationPassword: "newReplicationPassword123"

passwordUpdateJob:
  enabled: true

In this example we use two existing secrets (new-password-secret and previous-password-secret) to update the passwords:

auth:
  existingSecret: new-password-secret

passwordUpdateJob:
  enabled: true
  previousPasswords:
    existingSecret: previous-password-secret

You can add extra update commands using the passwordUpdateJob.extraCommands value.

⁠ postgresql.conf / pg_hba.conf files as configMap

This helm chart also supports to customize the PostgreSQL configuration file. You can add additional PostgreSQL configuration parameters using the primary.extendedConfiguration/readReplicas.extendedConfiguration parameters as a string. Alternatively, to replace the entire default configuration use primary.configuration.

You can also add a custom pg_hba.conf using the primary.pgHbaConfiguration parameter.

In addition to these options, you can also set an external ConfigMap with all the configuration files. This is done by setting the primary.existingConfigmap parameter. Note that this will override the two previous options.

⁠ Initialize a fresh instance

The Bitnami PostgreSQL⁠ image allows you to use your custom scripts to initialize a fresh instance. In order to execute the scripts, you can specify custom scripts using the primary.initdb.scripts parameter as a string.

In addition, you can also set an external ConfigMap with all the initialization scripts. This is done by setting the primary.initdb.scriptsConfigMap parameter. Note that this will override the two previous options. If your initialization scripts contain sensitive information such as credentials or passwords, you can use the primary.initdb.scriptsSecret parameter.

The allowed extensions are .sh, .sql and .sql.gz.

⁠ Securing traffic using TLS

TLS support can be enabled in the chart by specifying the tls. parameters while creating a release. The following parameters should be configured to properly enable the TLS support in the chart:

• tls.enabled: Enable TLS support. Defaults to false
• tls.certificatesSecret: Name of an existing secret that contains the certificates. No defaults.
• tls.certFilename: Certificate filename. No defaults.
• tls.certKeyFilename: Certificate key filename. No defaults.

For example:

• First, create the secret with the cetificates files:

  kubectl create secret generic certificates-tls-secret --from-file=./cert.crt --from-file=./cert.key --from-file=./ca.crt
  

  Copy

• Then, use the following parameters:

  volumePermissions.enabled=true
  tls.enabled=true
  tls.certificatesSecret="certificates-tls-secret"
  tls.certFilename="cert.crt"
  tls.certKeyFilename="cert.key"
  

  Copy

  Note TLS and VolumePermissions: PostgreSQL requires certain permissions on sensitive files (such as certificate keys) to start up. Due to an on-going issue⁠ regarding kubernetes permissions and the use of containerSecurityContext.runAsUser, you must enable volumePermissions to ensure everything works as expected.

⁠ Sidecars

If you need additional containers to run within the same pod as PostgreSQL (e.g. an additional metrics or logging exporter), you can do so via the sidecars config parameter. Simply define your container according to the Kubernetes container spec.

# For the PostgreSQL primary
primary:
  sidecars:
  - name: your-image-name
    image: your-image
    imagePullPolicy: Always
    ports:
    - name: portname
     containerPort: 1234
# For the PostgreSQL replicas
readReplicas:
  sidecars:
  - name: your-image-name
    image: your-image
    imagePullPolicy: Always
    ports:
    - name: portname
     containerPort: 1234

⁠ Metrics

The chart optionally can start a metrics exporter for prometheus⁠. The metrics endpoint (port 9187) is not exposed and it is expected that the metrics are collected from inside the k8s cluster using something similar as the described in the example Prometheus scrape configuration⁠.

The exporter allows to create custom metrics from additional SQL queries. See the Chart's values.yaml for an example and consult the exporters documentation⁠ for more details.

⁠ Use of global variables

In more complex scenarios, we may have the following tree of dependencies

                     +--------------+
                     |              |
        +------------+   Chart 1    +-----------+
        |            |              |           |
        |            --------+------+           |
        |                    |                  |
        |                    |                  |
        |                    |                  |
        |                    |                  |
        v                    v                  v
+-------+------+    +--------+------+  +--------+------+
|              |    |               |  |               |
|  PostgreSQL  |    |  Sub-chart 1  |  |  Sub-chart 2  |
|              |    |               |  |               |
+--------------+    +---------------+  +---------------+

The three charts below depend on the parent chart Chart 1. However, subcharts 1 and 2 may need to connect to PostgreSQL as well. In order to do so, subcharts 1 and 2 need to know the PostgreSQL credentials, so one option for deploying could be deploy Chart 1 with the following parameters:

postgresql.auth.username=testuser
subchart1.postgresql.auth.username=testuser
subchart2.postgresql.auth.username=testuser
postgresql.auth.password=testpass
subchart1.postgresql.auth.password=testpass
subchart2.postgresql.auth.password=testpass
postgresql.auth.database=testdb
subchart1.postgresql.auth.database=testdb
subchart2.postgresql.auth.database=testdb

If the number of dependent sub-charts increases, installing the chart with parameters can become increasingly difficult. An alternative would be to set the credentials using global variables as follows:

global.postgresql.auth.username=testuser
global.postgresql.auth.password=testpass
global.postgresql.auth.database=testdb

This way, the credentials will be available in all of the subcharts.

⁠ FIPS parameters

The FIPS parameters only have effect if you are using images from the Bitnami Secure Images catalog⁠.

For more information on this new support, please refer to the FIPS Compliance section⁠.

⁠ Backup and restore

To back up and restore Bitnami PostgreSQL Helm chart deployments on Kubernetes, you need to back up the persistent volumes from the source deployment and attach them to a new deployment using Velero⁠, a Kubernetes backup/restore tool.

These are the steps you will usually follow to back up and restore your PostgreSQL cluster data:

• Install Velero on the source and destination clusters.
• Use Velero to back up the PersistentVolumes (PVs) used by the deployment on the source cluster.
• Use Velero to restore the backed-up PVs on the destination cluster.
• Create a new deployment on the destination cluster with the same chart, deployment name, credentials and other parameters as the original. This new deployment will use the restored PVs and hence the original data.

Refer to our detailed tutorial on backing up and restoring PostgreSQL deployments on Kubernetes⁠ for more information.

⁠ NetworkPolicy

To enable network policy for PostgreSQL, install a networking plugin that implements the Kubernetes NetworkPolicy spec⁠, and set networkPolicy.enabled to true.

For Kubernetes v1.5 & v1.6, you must also turn on NetworkPolicy by setting the DefaultDeny namespace annotation. Note: this will enforce policy for all pods in the namespace:

kubectl annotate namespace default "net.beta.kubernetes.io/network-policy={\"ingress\":{\"isolation\":\"DefaultDeny\"}}"

With NetworkPolicy enabled, traffic will be limited to just port 5432.

For more precise policy, set networkPolicy.allowExternal=false. This will only allow pods with the generated client label to connect to PostgreSQL. This label will be displayed in the output of a successful install.

⁠ Differences between Bitnami PostgreSQL image and Docker Official⁠ image

• The Docker Official PostgreSQL image does not support replication. If you pass any replication environment variable, this would be ignored. The only environment variables supported by the Docker Official image are POSTGRES_USER, POSTGRES_DB, POSTGRES_PASSWORD, POSTGRES_INITDB_ARGS, POSTGRES_INITDB_WALDIR and PGDATA. All the remaining environment variables are specific to the Bitnami PostgreSQL image.
• The Bitnami PostgreSQL image is non-root by default. This requires that you run the pod with securityContext and updates the permissions of the volume with an initContainer. A key benefit of this configuration is that the pod follows security best practices and is prepared to run on Kubernetes distributions with hard security constraints like OpenShift.
• For OpenShift up to 4.10, let set the volume permissions, security context, runAsUser and fsGroup automatically by OpenShift and disable the predefined settings of the helm chart: primary.securityContext.enabled=false,primary.containerSecurityContext.enabled=false,volumePermissions.enabled=false,shmVolume.enabled=false
• For OpenShift 4.11 and higher, let set OpenShift the runAsUser and fsGroup automatically. Configure the pod and container security context to restrictive defaults and disable the volume permissions setup: primary. podSecurityContext.fsGroup=null,primary.podSecurityContext.seccompProfile.type=RuntimeDefault,primary.containerSecurityContext.runAsUser=null,primary.containerSecurityContext.allowPrivilegeEscalation=false,primary.containerSecurityContext.runAsNonRoot=true,primary.containerSecurityContext.seccompProfile.type=RuntimeDefault,primary.containerSecurityContext.capabilities.drop=['ALL'],volumePermissions.enabled=false,shmVolume.enabled=false

⁠ Setting Pod's affinity

This chart allows you to set your custom affinity using the XXX.affinity parameter(s). Find more information about Pod's affinity in the kubernetes documentation⁠.

As an alternative, you can use of the preset configurations for pod affinity, pod anti-affinity, and node affinity available at the bitnami/common⁠ chart. To do so, set the XXX.podAffinityPreset, XXX.podAntiAffinityPreset, or XXX.nodeAffinityPreset parameters.

⁠ Persistence

The Bitnami PostgreSQL⁠ image stores the PostgreSQL data and configurations at the /bitnami/postgresql path of the container.

Persistent Volume Claims are used to keep the data across deployments. This is known to work in GCE, AWS, and minikube. See the Parameters⁠ section to configure the PVC or to disable persistence.

If you already have data in it, you will fail to sync to standby nodes for all commits, details can refer to the code present in the container repository⁠. If you need to use those data, please covert them to sql and import after helm install finished.

⁠ Parameters

The following subsections list global, common, and component-specific parameters.

⁠ Global parameters

Note: the README for this chart is longer than the DockerHub length limit of 25000, so it has been trimmed. The full README can be found at https://techdocs.broadcom.com/us/en/vmware-tanzu/bitnami-secure-images/bitnami-secure-images/services/bsi-app-doc/apps-charts-postgresql-index.html⁠