MariaDB Cluster

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 incubator/mariadb-cluster

Introduction

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

Prerequisites

• Kubernetes 1.4+ with Beta APIs enabled
• 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 incubator/mariadb-cluster

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 tables lists the configurable parameters of the MariaDB chart and their default values.

Parameter	Description	Default
image.name	MariaDB image name	bitnami/mariadb
image.tag	MariaDB image tag	current version
image.pullPolicy	MariaDB image pull policy	IfNotPresent
service.type	Kubernetes service type	ClusterIP
service.port	MySQL service port	3306
root.password	Password for the root user	random 10 character alphanumeric string
db.user	Username of new user to create	nil
db.password	Password for the new user	random 10 character alphanumeric string if db.user is defined
db.name	Name for new database to create	my_database
replication.user	MariaDB replication user	replicator
replication.password	MariaDB replication user password	random 10 character alphanumeric string
master.antiAffinity	Master pod anti-affinity policy	soft
master.persistence.enabled	Enable persistence using a PersistentVolumeClaim	true
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.resources	CPU/Memory resource requests/limits for master node	{}
slave.replicas	Desired number of slave replicas	1
slave.antiAffinity	Slave pod anti-affinity policy	soft
slave.hpa.min	Minimum number of slave pods	1
slave.hpa.max	Maximum number of slave pods	3
slave.hpa.target.cpuPercentage	Target CPU percentage to trigger pod autoscaling	75
slave.resources	CPU/Memory resource requests/limits for slave nodes	{}
metrics.enabled	Start a side-car prometheus exporter	false
metrics.image	Exporter image name	prom/mysqld-exporter
metrics.imageTag	Exporter image tag	v0.10.0
metrics.imagePullPolicy	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 \
    incubator/mariadb-cluster

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 incubator/mariadb-cluster

Tip: You can use the default values.yaml

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.