bitnamicharts/mysql

Bitnami Secure Images Helm chart for MySQL

MySQL is a fast, reliable, scalable, and easy to use open source relational database system. Designed to handle mission-critical, heavy-load production applications.

Overview of MySQL

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

console
helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/mysql

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository.

Introduction

This chart bootstraps a https://github.com/bitnami/containers/tree/main/bitnami/mysql replication cluster deployment on a Kubernetes cluster using the Helm package manager.

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:

console
helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/mysql

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

These commands deploy MySQL on the Kubernetes cluster in the default configuration. The Parameters section lists the parameters that can be configured during installation.

Tip: List all releases using helm list

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 https://github.com/bitnami/charts/blob/main/bitnami/common/templates/_resources.tpl#L15. 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 https://github.com/prometheus/mysqld_exporter in all pods and will expose it via the MariaDB service. This service will 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 https://github.com/bitnami/charts/tree/main/bitnami/prometheus or the https://github.com/bitnami/charts/tree/main/bitnami/kube-prometheus 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:

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

Install the https://github.com/bitnami/charts/tree/main/bitnami/kube-prometheus 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.

Use a different MySQL 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.

Customize a new MySQL instance

The https://github.com/bitnami/containers/tree/main/bitnami/mysql image allows you to use your custom scripts to initialize a fresh instance. Custom scripts may be specified using the initdbScripts parameter. Alternatively, an external ConfigMap may be created with all the initialization scripts and the ConfigMap passed to the chart via the initdbScriptsConfigMap parameter. Note that this will override the initdbScripts parameter.

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

These scripts are treated differently depending on their extension. While .sh scripts are executed on all the nodes, .sql and .sql.gz scripts are only executed on the primary nodes. This is because .sh scripts support conditional tests to identify the type of node they are running on, while such tests are not supported in .sql or sql.gz files.

When using a .sh script, you may wish to perform a "one-time" action like creating a database. This can be achieved by adding a condition in the script to ensure that it is executed only on one node, as shown in the example below:

yaml
initdbScripts:
  my_init_script.sh: |
    #!/bin/bash
    if [[ $(hostname) == *primary* ]]; then
      echo "Primary node"
      password_aux="${MYSQL_ROOT_PASSWORD:-}"
      if [[ -f "${MYSQL_ROOT_PASSWORD_FILE:-}" ]]; then
          password_aux=$(cat "$MYSQL_ROOT_PASSWORD_FILE")
      fi
      mysql -P 3306 -uroot -p"$password_aux" -e "create database new_database";
    else
      echo "Secondary node"
    fi

Sidecars and Init Containers

If you have a need for additional containers to run within the same pod as MySQL, you can do so via the sidecars config parameter. Simply define your container according to the Kubernetes container spec.

yaml
sidecars:
  - name: your-image-name
    image: your-image
    imagePullPolicy: Always
    ports:
      - name: portname
        containerPort: 1234

Similarly, you can add extra init containers using the initContainers parameter.

yaml
initContainers:
  - name: your-image-name
    image: your-image
    imagePullPolicy: Always
    ports:
      - name: portname
        containerPort: 1234

Securing traffic using TLS

This chart supports encrypting communications using TLS. To enable this feature, set the tls.enabled.

It is necessary to create a secret containing the TLS certificates and pass it to the chart via the tls.existingSecret parameter. Every secret should contain a tls.crt and tls.key keys including the certificate and key files respectively and, optionally, a ca.crt key including the CA certificate. For example: create the secret with the certificates files:

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

You can manually create the required TLS certificates or relying on the chart auto-generation capabilities. The chart supports two different ways to auto-generate the required certificates:

• Using Helm capabilities. Enable this feature by setting tls.autoGenerated.enabled to true and tls.autoGenerated.engine to helm.
• Relying on CertManager (please note it's required to have CertManager installed in your K8s cluster). Enable this feature by setting tls.autoGenerated.enabled to true and tls.autoGenerated.engine to cert-manager. Please note it's supported to use an existing Issuer/ClusterIssuer for issuing the TLS certificates by setting the tls.autoGenerated.certManager.existingIssuer and tls.autoGenerated.certManager.existingIssuerKind parameters.

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 ROOT_PASSWORD placeholders)

shell
kubectl create secret generic SECRET_NAME --from-literal=password=PASSWORD --from-literal=root-password=ROOT_PASSWORD --dry-run -o yaml | kubectl apply -f -

Automated update using a password update job

The Bitnami MySQL provides a password update job that will automatically change the MySQL 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.rootPassword, 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 passwordUpdate.job.previousPasswords.rootPassword, passwordUpdate.job.previousPasswords.password, passwordUpdate.job.previousPasswords.replicationPassword (when applicable), setting auth.existingSecret.

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

yaml
architecture: "replication"

auth:
  user: "user"
  rootPassword: "newRootPassword123"
  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:

yaml
auth:
  existingSecret: new-password-secret

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

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

Network Policy config

To enable network policy for MySQL, 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:

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

With NetworkPolicy enabled, traffic will be limited to just port 3306.

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

Pod affinity

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

As an alternative, you can use the preset configurations for pod affinity, pod anti-affinity, and node affinity available at the https://github.com/bitnami/charts/tree/main/bitnami/common#affinities chart. To do so, set the XXX.podAffinityPreset, XXX.podAntiAffinityPreset, or XXX.nodeAffinityPreset parameters.

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 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. Find the instructions for using Velero in this guide.

Persistence

The https://github.com/bitnami/containers/tree/main/bitnami/mysql image stores the MySQL data and configurations at the /bitnami/mysql path of the container.

The chart mounts a Persistent Volume volume at this location. The volume is created using dynamic volume provisioning by default. An existing PersistentVolumeClaim can also be defined for this purpose.

If you encounter errors when working with persistent volumes, refer to our troubleshooting guide for persistent volumes.

Parameters

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

Global parameters

Common parameters

MySQL common 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 [***]