chinaxiaoming666 / -mysql-cluster

helm bitnami/mysql

MySQL

MySQL is a fast, reliable, scalable, and easy to use open-source relational database system. MySQL Server is intended for mission-critical, heavy-load production systems as well as for embedding into mass-deployed software.

TL;DR

$ helm repo add bitnami https://charts.bitnami.com/bitnami
$ helm install my-release bitnami/mysql

Introduction

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

Bitnami charts can be used with Kubeapps for deployment and management of Helm Charts in clusters. This Helm chart has been tested on top of Bitnami Kubernetes Production Runtime (BKPR). Deploy BKPR to get automated TLS certificates, logging and monitoring for your applications.

Prerequisites

• Kubernetes 1.12+
• Helm 3.1.0
• PV provisioner support in the underlying infrastructure

Installing the Chart

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

$ helm repo add bitnami https://charts.bitnami.com/bitnami
$ helm install my-release bitnami/mysql

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

Uninstalling the Chart

To uninstall/delete the my-release deployment:

$ helm delete my-release

The command removes all the Kubernetes components associated with the chart and deletes the release.

Parameters

The following table lists the configurable parameters of the MySQL chart and their default values.

Parameter	Description	Default
global.imageRegistry	Global Docker Image registry	nil
global.imagePullSecrets	Global Docker registry secret names as an array	[] (does not add image pull secrets to deployed pods)
global.storageClass	Global storage class for dynamic provisioning	nil

Common parameters

Parameter	Description	Default
nameOverride	String to partially override common.names.fullname	nil
fullnameOverride	String to fully override common.names.fullname	nil
clusterDomain	Default Kubernetes cluster domain	cluster.local
commonLabels	Labels to add to all deployed objects	nil
commonAnnotations	Annotations to add to all deployed objects	[]
schedulerName	Name of the scheduler (other than default) to dispatch pods	nil
extraDeploy	Array of extra objects to deploy with the release (evaluated as a template)	nil
priorityClassName	Name of priority class	nil

MySQL common parameters

Parameter	Description	Default
image.registry	MySQL image registry	docker.io
image.repository	MySQL image name	bitnami/mysql
image.tag	MySQL image tag	{TAG_NAME}
image.pullPolicy	MySQL image pull policy	IfNotPresent
image.pullSecrets	Specify docker-registry secret names as an array	[] (does not add image pull secrets to deployed pods)
image.debug	Specify if debug logs should be enabled	false
architecture	MySQL architecture (standalone or replication)	standalone
auth.rootPassword	Password for the root user. Ignored if existing secret is provided.	random 10 character alphanumeric string
auth.database	Name for a custom database to create	my_database
auth.username	Name for a custom user to create	""
auth.password	Password for the new user. Ignored if existing secret is provided	random 10 character long alphanumeric string
auth.replicationUser	MySQL replication user	nil
auth.replicationPassword	MySQL replication user password. Ignored if existing secret is provided	random 10 character long alphanumeric string
auth.forcePassword	Force users to specify required passwords	false
auth.usePasswordFiles	Mount credentials as a files instead of using an environment variable	false
auth.customPasswordFiles	Use custom password files when auth.usePasswordFiles is set to true. Define path for keys root and user, also define replicator if architecture is set to replication	{}
auth.existingSecret	Use existing secret for password details (auth.rootPassword, auth.password, auth.replicationPassword will be ignored and picked up from this secret). The secret has to contain the keys mysql-root-password, mysql-replication-password and mysql-password	nil
initdbScripts	Dictionary of initdb scripts	nil
initdbScriptsConfigMap	ConfigMap with the initdb scripts (Note: Overrides initdbScripts)	nil

MySQL Primary parameters

Parameter	Description	Default
primary.command	Override default container command on MySQL Primary container(s) (useful when using custom images)	nil
primary.args	Override default container args on MySQL Primary container(s) (useful when using custom images)	nil
primary.configuration	MySQL Primary configuration to be injected as ConfigMap	Check values.yaml file
primary.existingConfigmap	Name of existing ConfigMap with MySQL Primary configuration	nil
primary.updateStrategy	Update strategy type for the MySQL primary statefulset	RollingUpdate
primary.podAnnotations	Additional pod annotations for MySQL primary pods	{} (evaluated as a template)
primary.podLabels	Additional pod labels for MySQL primary pods	{} (evaluated as a template)
primary.podAffinityPreset	MySQL primary pod affinity preset. Ignored if primary.affinity is set. Allowed values: soft or hard	""
primary.podAntiAffinityPreset	MySQL primary pod anti-affinity preset. Ignored if primary.affinity is set. Allowed values: soft or hard	soft
primary.nodeAffinityPreset.type	MySQL primary node affinity preset type. Ignored if primary.affinity is set. Allowed values: soft or hard	""
primary.nodeAffinityPreset.key	MySQL primary node label key to match Ignored if primary.affinity is set.	""
primary.nodeAffinityPreset.values	MySQL primary node label values to match. Ignored if primary.affinity is set.	[]
primary.affinity	Affinity for MySQL primary pods assignment	{} (evaluated as a template)
primary.nodeSelector	Node labels for MySQL primary pods assignment	{} (evaluated as a template)
primary.tolerations	Tolerations for MySQL primary pods assignment	[] (evaluated as a template)
primary.podSecurityContext.enabled	Enable security context for MySQL primary pods	true
primary.podSecurityContext.fsGroup	Group ID for the mounted volumes' filesystem	1001
primary.containerSecurityContext.enabled	MySQL primary container securityContext	true
primary.containerSecurityContext.runAsUser	User ID for the MySQL primary container	1001
primary.livenessProbe	Liveness probe configuration for MySQL primary containers	Check values.yaml file
primary.readinessProbe	Readiness probe configuration for MySQL primary containers	Check values.yaml file
primary.customLivenessProbe	Override default liveness probe for MySQL primary containers	nil
primary.customReadinessProbe	Override default readiness probe for MySQL primary containers	nil
primary.resources.limits	The resources limits for MySQL primary containers	{}
primary.resources.requests	The requested resources for MySQL primary containers	{}
primary.extraEnvVars	Extra environment variables to be set on MySQL primary containers	{}
primary.extraEnvVarsCM	Name of existing ConfigMap containing extra env vars for MySQL primary containers	nil
primary.extraEnvVarsSecret	Name of existing Secret containing extra env vars for MySQL primary containers	nil
primary.extraFlags	MySQL primary additional command line flags	nil
primary.persistence.enabled	Enable persistence on MySQL primary replicas using a PersistentVolumeClaim	true
primary.persistence.existingClaim	Name of an existing PersistentVolumeClaim for MySQL primary replicas	nil
primary.persistence.annotations	MySQL primary persistent volume claim annotations	{} (evaluated as a template)
primary.persistence.storageClass	MySQL primary persistent volume storage Class	nil
primary.persistence.accessModes	MySQL primary persistent volume access Modes	[ReadWriteOnce]
primary.persistence.size	MySQL primary persistent volume size	8Gi
primary.persistence.selector	Selector to match an existing Persistent Volume	{} (evaluated as a template)
primary.initContainers	Add additional init containers for the MySQL Primary pod(s)	{} (evaluated as a template)
primary.sidecars	Add additional sidecar containers for the MySQL Primary pod(s)	{} (evaluated as a template)
primary.extraVolumeMounts	Optionally specify extra list of additional volumeMounts for the MySQL Primary container(s)	{}
primary.extraVolumes	Optionally specify extra list of additional volumes to the MySQL Primary pod(s)	{}
primary.service.type	MySQL Primary K8s service type	ClusterIP
primary.service.clusterIP	MySQL Primary K8s service clusterIP IP	nil
primary.service.port	MySQL Primary K8s service port	3306
primary.service.nodePort	MySQL Primary K8s service node port	nil
primary.service.loadBalancerIP	MySQL Primary loadBalancerIP if service type is LoadBalancer	nil
primary.service.loadBalancerSourceRanges	Address that are allowed when MySQL Primary service is LoadBalancer	[]
primary.pdb.create	Enable/disable a Pod Disruption Budget creation for MySQL primary pods	false
primary.pdb.minAvailable	Minimum number/percentage of MySQL primary pods that should remain scheduled	1
primary.pdb.maxUnavailable	Maximum number/percentage of MySQL primary pods that may be made unavailable	nil

MySQL Secondary parameters

Parameter	Description	Default
secondary.command	Override default container command on MySQL Secondary container(s) (useful when using custom images)	nil
secondary.args	Override default container args on MySQL Secondary container(s) (useful when using custom images)	nil
secondary.configuration	MySQL Secondary configuration to be injected as ConfigMap	Check values.yaml file
secondary.existingConfigmap	Name of existing ConfigMap with MySQL Secondary configuration	nil
secondary.replicaCount	Number of MySQL secondary replicas	1
secondary.updateStrategy	Update strategy type for the MySQL secondary statefulset	RollingUpdate
secondary.podAnnotations	Additional pod annotations for MySQL secondary pods	{} (evaluated as a template)
secondary.podLabels	Additional pod labels for MySQL secondary pods	{} (evaluated as a template)
secondary.podAffinityPreset	MySQL secondary pod affinity preset. Ignored if secondary.affinity is set. Allowed values: soft or hard	""
secondary.podAntiAffinityPreset	MySQL secondary pod anti-affinity preset. Ignored if secondary.affinity is set. Allowed values: soft or hard	soft
secondary.nodeAffinityPreset.type	MySQL secondary node affinity preset type. Ignored if secondary.affinity is set. Allowed values: soft or hard	""
secondary.nodeAffinityPreset.key	MySQL secondary node label key to match Ignored if secondary.affinity is set.	""
secondary.nodeAffinityPreset.values	MySQL secondary node label values to match. Ignored if secondary.affinity is set.	[]
secondary.affinity	Affinity for MySQL secondary pods assignment	{} (evaluated as a template)
secondary.nodeSelector	Node labels for MySQL secondary pods assignment	{} (evaluated as a template)
secondary.tolerations	Tolerations for MySQL secondary pods assignment	[] (evaluated as a template)
secondary.podSecurityContext.enabled	Enable security context for MySQL secondary pods	true
secondary.podSecurityContext.fsGroup	Group ID for the mounted volumes' filesystem	1001
secondary.containerSecurityContext.enabled	MySQL secondary container securityContext	true
secondary.containerSecurityContext.runAsUser	User ID for the MySQL secondary container	1001
secondary.livenessProbe	Liveness probe configuration for MySQL secondary containers	Check values.yaml file
secondary.readinessProbe	Readiness probe configuration for MySQL secondary containers	Check values.yaml file
secondary.customLivenessProbe	Override default liveness probe for MySQL secondary containers	nil
secondary.customReadinessProbe	Override default readiness probe for MySQL secondary containers	nil
secondary.resources.limits	The resources limits for MySQL secondary containers	{}
secondary.resources.requests	The requested resources for MySQL secondary containers	{}
secondary.extraEnvVars	Extra environment variables to be set on MySQL secondary containers	{}
secondary.extraEnvVarsCM	Name of existing ConfigMap containing extra env vars for MySQL secondary containers	nil
secondary.extraEnvVarsSecret	Name of existing Secret containing extra env vars for MySQL secondary containers	nil
secondary.extraFlags	MySQL secondary additional command line flags	nil
secondary.extraFlags	MySQL secondary additional command line flags	nil
secondary.persistence.enabled	Enable persistence on MySQL secondary replicas using a PersistentVolumeClaim	true
secondary.persistence.annotations	MySQL secondary persistent volume claim annotations	{} (evaluated as a template)
secondary.persistence.storageClass	MySQL secondary persistent volume storage Class	nil
secondary.persistence.accessModes	MySQL secondary persistent volume access Modes	[ReadWriteOnce]
secondary.persistence.size	MySQL secondary persistent volume size	8Gi
secondary.persistence.selector	Selector to match an existing Persistent Volume	{} (evaluated as a template)
secondary.initContainers	Add additional init containers for the MySQL secondary pod(s)	{} (evaluated as a template)
secondary.sidecars	Add additional sidecar containers for the MySQL secondary pod(s)	{} (evaluated as a template)
secondary.extraVolumeMounts	Optionally specify extra list of additional volumeMounts for the MySQL secondary container(s)	{}
secondary.extraVolumes	Optionally specify extra list of additional volumes to the MySQL secondary pod(s)	{}
secondary.service.type	MySQL secondary K8s service type	ClusterIP
secondary.service.clusterIP	MySQL secondary K8s service clusterIP IP	nil
secondary.service.port	MySQL secondary K8s service port	3306
secondary.service.nodePort	MySQL secondary K8s service node port	nil
secondary.service.loadBalancerIP	MySQL secondary loadBalancerIP if service type is LoadBalancer	nil
secondary.service.loadBalancerSourceRanges	Address that are allowed when MySQL secondary service is LoadBalancer	[]
secondary.pdb.create	Enable/disable a Pod Disruption Budget creation for MySQL secondary pods	false
secondary.pdb.minAvailable	Minimum number/percentage of MySQL secondary pods that should remain scheduled	1
secondary.pdb.maxUnavailable	Maximum number/percentage of MySQL secondary pods that may be made unavailable	nil

RBAC parameters

Parameter	Description	Default
serviceAccount.create	Enable the creation of a ServiceAccount for MySQL pods	true
serviceAccount.name	Name of the created ServiceAccount	Generated using the common.names.fullname template
serviceAccount.annotations	Annotations for MySQL Service Account	{} (evaluated as a template)
rbac.create	Weather to create & use RBAC resources or not	false

Volume Permissions parameters

Parameter	Description	Default
volumePermissions.enabled	Enable init container that changes the owner and group of the persistent volume(s) mountpoint to runAsUser:fsGroup	false
volumePermissions.image.registry	Init container volume-permissions image registry	docker.io
volumePermissions.image.repository	Init container volume-permissions image name	bitnami/minideb
volumePermissions.image.tag	Init container volume-permissions image tag	buster
volumePermissions.image.pullPolicy	Init container volume-permissions image pull policy	Always
volumePermissions.image.pullSecrets	Specify docker-registry secret names as an array	[] (does not add image pull secrets to deployed pods)
volumePermissions.resources.limits	Init container volume-permissions resource limits	{}
volumePermissions.resources.requests	Init container volume-permissions resource requests	{}

Metrics parameters

Parameter	Description	Default
metrics.enabled	Start a side-car prometheus exporter	false
metrics.image.registry	Exporter image registry	docker.io
metrics.image.repository	Exporter image name	bitnami/mysqld-exporter
metrics.image.tag	Exporter image tag	{TAG_NAME}
metrics.image.pullPolicy	Exporter image pull policy	IfNotPresent
metrics.extraArgs.primary	Extra args to be passed to mysqld_exporter on Primary pods	[]
metrics.extraArgs.secondary	Extra args to be passed to mysqld_exporter on Secondary pods	[]
metrics.service.type	Kubernetes service type for MySQL Prometheus Exporter	ClusterIP
metrics.service.port	MySQL Prometheus Exporter service port	9104
metrics.service.annotations	Prometheus exporter svc annotations	{prometheus.io/scrape: "true", prometheus.io/port: "9104"}
metrics.resources.limits	The resources limits for MySQL prometheus exporter containers	{}
metrics.resources.requests	The requested resources for MySQL prometheus exporter containers	{}
metrics.livenessProbe	Liveness probe configuration for MySQL prometheus exporter containers	Check values.yaml file
metrics.readinessProbe	Readiness probe configuration for MySQL prometheus exporter containers	Check values.yaml file
metrics.serviceMonitor.enabled	Create ServiceMonitor Resource for scraping metrics using PrometheusOperator	false
metrics.serviceMonitor.namespace	Namespace which Prometheus is running in	nil
metrics.serviceMonitor.interval	Interval at which metrics should be scraped	30s
metrics.serviceMonitor.scrapeTimeout	Specify the timeout after which the scrape is ended	nil
metrics.serviceMonitor.relabellings	Specify Metric Relabellings to add to the scrape endpoint	nil
metrics.serviceMonitor.honorLabels	honorLabels chooses the metric's labels on collisions with target labels.	false
metrics.serviceMonitor.additionalLabels	Used to pass Labels that are required by the Installed Prometheus Operator	{}
metrics.serviceMonitor.release	Used to pass Labels release that sometimes should be custom for Prometheus Operator	nil

The above parameters map to the env variables defined in bitnami/mysql. For more information please refer to the bitnami/mysql image documentation.

Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,

$ helm install my-release \
  --set auth.rootPassword=secretpassword,auth.database=app_database \
    bitnami/mysql

The above command sets the MySQL root account password to secretpassword. Additionally it creates a database named app_database.

Alternatively, a YAML file that specifies the values for the parameters can be provided while installing the chart. For example,

$ helm install my-release -f values.yaml bitnami/mysql

Tip: You can use the default values.yaml

Configuration and installation details

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.

Change MySQL version

To modify the MySQL version used in this chart you can specify a valid image tag using the image.tag parameter. For example, image.tag=X.Y.Z. This approach is also applicable to other images like exporters.

Initialize a fresh instance

The Bitnami MySQL image allows you to use your custom scripts to initialize a fresh instance. In order to execute the scripts, they must be located inside the chart folder files/docker-entrypoint-initdb.d so they can be consumed as a ConfigMap.

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

Take into account those scripts are treated differently depending on the extension. While the .sh scripts are executed in all the nodes; the .sql and .sql.gz scripts are only executed in the primary nodes. The reason behind this differentiation is that the .sh scripts allow adding conditions to determine what is the node running the script, while these conditions can't be set using .sql nor sql.gz files. This way it is possible to cover different use cases depending on their needs.

If using a .sh script you want to do a "one-time" action like creating a database, you need to add a condition in your .sh script to be executed only in one of the nodes, such as

initdbScripts:
  my_init_script.sh: |
     #!/bin/sh
     if [[ $(hostname) == *master* ]]; then
       echo "Master node"
       mysql -P 3306 -uroot -prandompassword -e "create database new_database";
     else
       echo "No master 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.

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.

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

Persistence

The 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 be defined.

Adjust permissions of persistent volume mountpoint

As the image run as non-root by default, it is necessary to adjust the ownership of the persistent volume so that the container can write data into it.

By default, the chart is configured to use Kubernetes Security Context to automatically change the ownership of the volume. However, this feature does not work in all Kubernetes distributions. As an alternative, this chart supports using an initContainer to change the ownership of the volume before mounting it in the final destination.

You can enable this initContainer by setting volumePermissions.enabled to true.

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.

Troubleshooting

Find more information about how to deal with common errors related to Bitnami’s Helm charts in this troubleshooting guide.

Upgrading

It's necessary to set the auth.rootPassword parameter when upgrading for readiness/liveness probes to work properly. When you install this chart for the first time, some notes will be displayed providing the credentials you must use under the 'Administrator credentials' section. Please note down the password and run the command below to upgrade your chart:

$ helm upgrade my-release bitnami/mysql --set auth.rootPassword=[ROOT_PASSWORD]

| Note: you need to substitute the placeholder [ROOT_PASSWORD] with the value obtained in the installation notes.

To 8.0.0

• Several parameters were renamed or disappeared in favor of new ones on this major version:
  • The terms master and slave have been replaced by the terms primary and secondary. Therefore, parameters prefixed with master or slave are now prefixed with primary or secondary, respectively.
  • Credentials parameters are reorganized under the auth parameter.
  • replication.enabled parameter is deprecated in favor of architecture parameter that accepts two values: standalone and replication.
• Chart labels were adapted to follow the Helm charts standard labels.
• This version also introduces bitnami/common, a library chart as a dependency. More documentation about this new utility could be found here. Please, make sure that you have updated the chart dependencies before executing any upgrade.

Consequences:

• Backwards compatibility is not guaranteed. To upgrade to 8.0.0, install a new release of the MySQL chart, and migrate the data from your previous release. You have 2 alternatives to do so:
  • Create a backup of the database, and restore it on the new release using tools such as mysqldump.
  • Reuse the PVC used to hold the master data on your previous release. To do so, use the primary.persistence.existingClaim parameter. The following example assumes that the release name is mysql:

$ helm install mysql bitnami/mysql --set auth.rootPassword=[ROOT_PASSWORD] --set primary.persistence.existingClaim=[EXISTING_PVC]

| Note: you need to substitute the placeholder [EXISTING_PVC] with the name of the PVC used on your previous release, and [ROOT_PASSWORD] with the root password used in your previous release.

To 7.0.0

On November 13, 2020, Helm v2 support was formally finished, this major version is the result of the required changes applied to the Helm Chart to be able to incorporate the different features added in Helm v3 and to be consistent with the Helm project itself regarding the Helm v2 EOL.

What changes were introduced in this major version?

• Previous versions of this Helm Chart use apiVersion: v1 (installable by both Helm 2 and 3), this Helm Chart was updated to apiVersion: v2 (installable by Helm 3 only). Here you can find more information about the apiVersion field.
• The different fields present in the Chart.yaml file has been ordered alphabetically in a homogeneous way for all the Bitnami Helm Charts

Considerations when upgrading to this version

• If you want to upgrade to this version from a previous one installed with Helm v3, you shouldn't face any issues
• If you want to upgrade to this version using Helm v2, this scenario is not supported as this version doesn't support Helm v2 anymore
• If you installed the previous version with Helm v2 and wants to upgrade to this version with Helm v3, please refer to the official Helm documentation about migrating from Helm v2 to v3

Useful links

• https://docs.bitnami.com/tutorials/resolve-helm2-helm3-post-migration-issues/
• https://helm.sh/docs/topics/v2_v3_migration/
• https://helm.sh/blog/migrate-from-helm-v2-to-helm-v3/

To 3.0.0

Backwards compatibility is not guaranteed unless you modify the labels used on the chart's deployments. Use the workaround below to upgrade from versions previous to 3.0.0. The following example assumes that the release name is mysql:

$ kubectl delete statefulset mysql-master --cascade=false
$ kubectl delete statefulset mysql-slave --cascade=false