kubeasz/manifests/mariadb-cluster/mariadb

MariaDB

MariaDB is one of the most popular database servers in the world. It’s made by the original developers of MySQL and guaranteed to stay open source. Notable users include Wikipedia, Facebook and Google.

MariaDB is developed as open source software and as a relational database it provides an SQL interface for accessing data. The latest versions of MariaDB also include GIS and JSON features.

TL;DR

$ helm install stable/mariadb

Introduction

This chart bootstraps a MariaDB 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.

Prerequisites

• Kubernetes 1.10+
• PV provisioner support in the underlying infrastructure

Installing the Chart

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

$ helm install --name my-release stable/mariadb

The command deploys MariaDB on the Kubernetes cluster in the default configuration. The configuration 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.

Configuration

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

Parameter	Description	Default
global.imageRegistry	Global Docker image registry	nil
image.registry	MariaDB image registry	docker.io
image.repository	MariaDB Image name	bitnami/mariadb
image.tag	MariaDB Image tag	{VERSION}
image.pullPolicy	MariaDB image pull policy	Always if imageTag is latest, else 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
service.type	Kubernetes service type	ClusterIP
service.clusterIp	Specific cluster IP when service type is cluster IP. Use None for headless service	nil
service.port	MySQL service port	3306
serviceAccount.create	Specifies whether a ServiceAccount should be created	false
serviceAccount.name	The name of the ServiceAccount to create	Generated using the mariadb.fullname template
securityContext.enabled	Enable security context	true
securityContext.fsGroup	Group ID for the container	1001
securityContext.runAsUser	User ID for the container	1001
existingSecret	Use Existing secret for Password details (rootUser.password, db.password, replication.password will be ignored and picked up from this secret)
rootUser.password	Password for the root user. Ignored if existing secret is provided.	random 10 character alphanumeric string
rootUser.forcePassword	Force users to specify a password	false
db.user	Username of new user to create	nil
db.password	Password for the new user. Ignored if existing secret is provided.	random 10 character alphanumeric string if db.user is defined
db.name	Name for new database to create	my_database
replication.enabled	MariaDB replication enabled	true
replication.user	MariaDB replication user	replicator
replication.password	MariaDB replication user password. Ignored if existing secret is provided.	random 10 character alphanumeric string
initdbScripts	List of initdb scripts	nil
initdbScriptsConfigMap	ConfigMap with the initdb scripts (Note: Overrides initdbScripts)	nil
master.annotations[].key	key for the the annotation list item	nil
master.annotations[].value	value for the the annotation list item	nil
master.affinity	Master affinity (in addition to master.antiAffinity when set)	{}
master.antiAffinity	Master pod anti-affinity policy	soft
master.tolerations	List of node taints to tolerate (master)	[]
master.persistence.enabled	Enable persistence using PVC	true
master.persistence.existingClaim	Provide an existing PersistentVolumeClaim	nil
master.persistence.mountPath	Path to mount the volume at	/bitnami/mariadb
master.persistence.annotations	Persistent Volume Claim annotations	{}
master.persistence.storageClass	Persistent Volume Storage Class	``
master.persistence.accessModes	Persistent Volume Access Modes	[ReadWriteOnce]
master.persistence.size	Persistent Volume Size	8Gi
master.extraInitContainers	Additional init containers as a string to be passed to the tpl function (master)
master.config	Config file for the MariaDB Master server	_default values in the values.yaml file_
master.resources	CPU/Memory resource requests/limits for master node	{}
master.livenessProbe.enabled	Turn on and off liveness probe (master)	true
master.livenessProbe.initialDelaySeconds	Delay before liveness probe is initiated (master)	120
master.livenessProbe.periodSeconds	How often to perform the probe (master)	10
master.livenessProbe.timeoutSeconds	When the probe times out (master)	1
master.livenessProbe.successThreshold	Minimum consecutive successes for the probe (master)	1
master.livenessProbe.failureThreshold	Minimum consecutive failures for the probe (master)	3
master.readinessProbe.enabled	Turn on and off readiness probe (master)	true
master.readinessProbe.initialDelaySeconds	Delay before readiness probe is initiated (master)	30
master.readinessProbe.periodSeconds	How often to perform the probe (master)	10
master.readinessProbe.timeoutSeconds	When the probe times out (master)	1
master.readinessProbe.successThreshold	Minimum consecutive successes for the probe (master)	1
master.readinessProbe.failureThreshold	Minimum consecutive failures for the probe (master)	3
slave.replicas	Desired number of slave replicas	1
slave.annotations[].key	key for the the annotation list item	nil
slave.annotations[].value	value for the the annotation list item	nil
slave.affinity	Slave affinity (in addition to slave.antiAffinity when set)	{}
slave.antiAffinity	Slave pod anti-affinity policy	soft
slave.tolerations	List of node taints to tolerate for (slave)	[]
slave.persistence.enabled	Enable persistence using a PersistentVolumeClaim	true
slave.persistence.annotations	Persistent Volume Claim annotations	{}
slave.persistence.storageClass	Persistent Volume Storage Class	``
slave.persistence.accessModes	Persistent Volume Access Modes	[ReadWriteOnce]
slave.persistence.size	Persistent Volume Size	8Gi
slave.extraInitContainers	Additional init containers as a string to be passed to the tpl function (slave)
slave.config	Config file for the MariaDB Slave replicas	_default values in the values.yaml file_
slave.resources	CPU/Memory resource requests/limits for slave node	{}
slave.livenessProbe.enabled	Turn on and off liveness probe (slave)	true
slave.livenessProbe.initialDelaySeconds	Delay before liveness probe is initiated (slave)	120
slave.livenessProbe.periodSeconds	How often to perform the probe (slave)	10
slave.livenessProbe.timeoutSeconds	When the probe times out (slave)	1
slave.livenessProbe.successThreshold	Minimum consecutive successes for the probe (slave)	1
slave.livenessProbe.failureThreshold	Minimum consecutive failures for the probe (slave)	3
slave.readinessProbe.enabled	Turn on and off readiness probe (slave)	true
slave.readinessProbe.initialDelaySeconds	Delay before readiness probe is initiated (slave)	45
slave.readinessProbe.periodSeconds	How often to perform the probe (slave)	10
slave.readinessProbe.timeoutSeconds	When the probe times out (slave)	1
slave.readinessProbe.successThreshold	Minimum consecutive successes for the probe (slave)	1
slave.readinessProbe.failureThreshold	Minimum consecutive failures for the probe (slave)	3
metrics.enabled	Start a side-car prometheus exporter	false
metrics.image.registry	Exporter image registry	docker.io
metrics.image.repository	Exporter image name	prom/mysqld-exporter
metrics.image.tag	Exporter image tag	v0.10.0
metrics.image.pullPolicy	Exporter image pull policy	IfNotPresent
metrics.resources	Exporter resource requests/limit	nil

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

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

$ helm install --name my-release \
  --set root.password=secretpassword,user.database=app_database \
    stable/mariadb

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

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

$ helm install --name my-release -f values.yaml stable/mariadb

Tip: You can use the default values.yaml

Initialize a fresh instance

The Bitnami MariaDB 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.

Alternatively, you can specify custom scripts using the initdbScripts parameter as dict.

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

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

Persistence

The Bitnami MariaDB image stores the MariaDB data and configurations at the /bitnami/mariadb 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.

Extra Init Containers

The feature allows for specifying a template string for a initContainer in the master/slave pod. Usecases include situations when you need some pre-run setup. For example, in IKS (IBM Cloud Kubernetes Service), non-root users do not have write permission on the volume mount path for NFS-powered file storage. So, you could use a initcontainer to chown the mount. See a example below, where we add an initContainer on the master pod that reports to an external resource that the db is going to starting. values.yaml

master:
  extraInitContainers: |
    - name: initcontainer
      image: alpine:latest
      command: ["/bin/sh", "-c"]
      args:
        - curl http://api-service.local/db/starting;    

Upgrading

It's necessary to set the rootUser.password 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 stable/mariadb --set rootUser.password=[ROOT_PASSWORD]

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

To 5.0.0

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 5.0.0. The following example assumes that the release name is mariadb:

$ kubectl delete statefulset opencart-mariadb --cascade=false