Usage

Requirements

A distributed Apache HBase installation depends on a running Apache ZooKeeper and HDFS cluster. See the documentation for the Stackable Operator for Apache HDFS how to set up these clusters.

Deployment of an Apache HBase cluster

An Apache HBase cluster can be created with the following cluster specification:

apiVersion: hbase.stackable.tech/v1alpha1
kind: HbaseCluster
metadata:
  name: simple-hbase
spec:
  version: 2.4.12-stackable0.1.0
  hdfsConfigMapName: simple-hdfs-namenode-default
  zookeeperConfigMapName: simple-hbase-znode
  config:
    hbaseOpts:
    hbaseRootdir: /hbase
  masters:
    roleGroups:
      default:
        selector:
          matchLabels:
            kubernetes.io/os: linux
        replicas: 1
  regionServers:
    roleGroups:
      default:
        selector:
          matchLabels:
            kubernetes.io/os: linux
        replicas: 1
  restServers:
    roleGroups:
      default:
        selector:
          matchLabels:
            kubernetes.io/os: linux
        replicas: 1
---
apiVersion: zookeeper.stackable.tech/v1alpha1
kind: ZookeeperZnode
metadata:
  name: simple-hbase-znode
spec:
  clusterRef:
    name: simple-zk

  • hdfsConfigMapName references the config map created by the Stackable HDFS operator.

  • zookeeperConfigMapName references the config map created by the Stackable ZooKeeper operator.

  • hbaseOpts is mapped to the environment variable HBASE_OPTS in hbase-env.sh.

  • hbaseRootdir is mapped to hbase.rootdir in hbase-site.xml.

Please note that the version you need to specify is not only the version of HBase which you want to roll out, but has to be amended with a Stackable version as shown. This Stackable version is the version of the underlying container image which is used to execute the processes. For a list of available versions please check our image registry. It should generally be safe to simply use the latest image version that is available.

Monitoring

The managed HBase instances are automatically configured to export Prometheus metrics. See Monitoring for more details.

Configuration Overrides

The cluster definition also supports overriding configuration properties and environment variables, either per role or per role group, where the more specific override (role group) has precedence over the less specific one (role).

Overriding certain properties which are set by operator can interfere with the operator and can lead to problems.

Configuration Properties

For a role or role group, at the same level of config, you can specify: configOverrides for the following files:

  • hbase-site.xml

  • hbase-env.sh

For example, if you want to set the hbase.rest.threads.min to 4 and the HBASE_HEAPSIZE to two GB adapt the restServers section of the cluster resource like so:

restServers:
  roleGroups:
    default:
      config: {}
      configOverrides:
        hbase-site.xml:
          hbase.rest.threads.min: "4"
        hbase-env.sh:
          HBASE_HEAPSIZE: "2G"
      replicas: 1

Just as for the config, it is possible to specify this at role level as well:

restServers:
  configOverrides:
    hbase-site.xml:
      hbase.rest.threads.min: "4"
    hbase-env.sh:
      HBASE_HEAPSIZE: "2G"
  roleGroups:
    default:
      config: {}
      replicas: 1

All override property values must be strings. The properties will be formatted and escaped correctly into the XML file, respectively inserted as is into the env.sh file.

For a full list of configuration options we refer to the HBase Configuration Documentation.