MapR Distribution Plugin¶

Operation¶

The MapR Plugin performs the following four primary functions during cluster creation:

1. MapR components deployment - the plugin manages the deployment of the required software to the target VMs
2. Services Installation - MapR services are installed according to provided roles list
3. Services Configuration - the plugin combines default settings with user provided settings
4. Services Start - the plugin starts appropriate services according to specified roles

Images¶

The Sahara MapR plugin can make use of either minimal (operating system only) images or pre-populated MapR images. The base requirement for both is that the image is cloud-init enabled and contains a supported operating system (see http://maprdocs.mapr.com/home/InteropMatrix/r_os_matrix.html).

The advantage of a pre-populated image is that provisioning time is reduced, as packages do not need to be downloaded which make up the majority of the time spent in the provisioning cycle. In addition, provisioning large clusters will put a burden on the network as packages for all nodes need to be downloaded from the package repository.

For more information about MapR images, refer to https://github.com/openstack/sahara-image-elements.

There are VM images provided for use with the MapR Plugin, that can also be built using the tools available in sahara-image-elements: https://s3-us-west-2.amazonaws.com/sahara-images/index.html

MapR plugin needs an image to be tagged in Sahara Image Registry with two tags: ‘mapr’ and ‘<MapR version>’ (e.g. ‘5.2.0.mrv2’).

The default username specified for these images is different for each distribution:

Hadoop Version Support¶

The MapR plugin currently supports Hadoop 2.7.0 (5.2.0.mrv2).

Cluster Validation¶

When the user creates or scales a Hadoop cluster using a mapr plugin, the cluster topology requested by the user is verified for consistency.

Every MapR cluster must contain:

• at least 1 CLDB process
• exactly 1 Webserver process
• odd number of ZooKeeper processes but not less than 1
• FileServer process on every node
• at least 1 ephemeral drive (then you need to specify the ephemeral drive in the flavor not on the node group template creation) or 1 Cinder volume per instance

Every Hadoop cluster must contain exactly 1 Oozie process

Every MapReduce v1 cluster must contain:

• at least 1 JobTracker process
• at least 1 TaskTracker process

Every MapReduce v2 cluster must contain:

• exactly 1 ResourceManager process
• exactly 1 HistoryServer process
• at least 1 NodeManager process

Every Spark cluster must contain:

• exactly 1 Spark Master process
• exactly 1 Spark HistoryServer process
• at least 1 Spark Slave (worker) process

HBase service is considered valid if:

• cluster has at least 1 HBase-Master process
• cluster has at least 1 HBase-RegionServer process

Hive service is considered valid if:

• cluster has exactly 1 HiveMetastore process
• cluster has exactly 1 HiveServer2 process

Hue service is considered valid if:

• cluster has exactly 1 Hue process
• Hue process resides on the same node as HttpFS process

HttpFS service is considered valid if cluster has exactly 1 HttpFS process

Sqoop service is considered valid if cluster has exactly 1 Sqoop2-Server process

The MapR Plugin¶

For more information, please contact MapR.