Data Engineering clusters

Data Engineering cluster definition

This Data Engineering template includes a standalone deployment of Spark and Hive, as well as Apache Oozie for job scheduling and orchestration, Apache Livy for remote job submission, and Hue and Apache Zeppelin for job authoring and interactive analysis.

Cluster definition names

Data Engineering for AWS
Data Engineering HA - Spark3 for AWS

See the architectural information below for the Data Engineering HA clusters
Data Engineering Spark3 for AWS

Cluster template name

Data Engineering: Apache Spark3, Apache Hive, Apache Oozie
note
This cluster template was formerly named "Data Engineering: Apache Spark, Apache Hive, Apache Oozie."
Data Engineering: HA: Apache Spark3, Apache Hive, Apache Oozie
note
This cluster template was formerly named "Data Engineering: HA: Apache Spark, Apache Hive, Apache Oozie."

See the architectural information below for the Data Engineering HA clusters
Data Engineering: Apache Spark3, Apache Hive, Apache Oozie
note
The "Data Engineering: Apache Spark3" cluster template is deleted. Therefore, the "Data Engineering: Apache Spark3, Apache Hive, Apache Oozie" cluster template can be used instead.

Included services

HDFS
Hive
Hue
Livy
Spark 3
Yarn
Zeppelin
ZooKeeper
Oozie is supported for Spark 3 as of Runtime version 7.2.18
Hive Warehouse Connector is supported as of Runtime version 7.2.16.

Compatible runtime version

7.2.16, 7.2.17, 7.2.18

Topology of the Data Engineering cluster

Topology is a set of host groups that are defined in the cluster template and cluster definition used by Data Engineering. Data Engineering uses the following topology:

Host group	Description	Node configuration
Master	The master host group runs the components for managing the cluster resources including Cloudera Manager (CM), Name Node, Resource Manager, as well as other master components such HiveServer2, HMS, Hue etc.	1 For Runtime versions earlier than 7.2.14: AWS : m5.4xlarge; gp2 - 100 GB For Runtime versions 7.2.14+ DE, DE Spark3, and DE HA: AWS : m5.4xlarge; gp2 - 100 GB
Worker	The worker host group runs the components that are used for executing processing tasks (such as NodeManager) and handling storing data in HDFS such as DataNode.	3 For Runtime versions earlier than 7.2.14: AWS : m5.2xlarge; gp2 - 100 GB For Runtime versions 7.2.14+ DE and DE Spark3: AWS: r5d.2xlarge - (gp2/EBS volumes) DE HA: AWS: r5d.4xlarge - (gp2/EBS volumes)
Compute	The compute host group can optionally be used for running data processing tasks (such as NodeManager). By default the number of compute nodes is set to 1 for proper configurations of YARN containers. This node group can be scaled down to 0 when there are no compute needs. Additionally, if load-based auto-scaling is enabled with minimum count set to 0, the compute nodegroup will be resized to 0 automatically.	0+ For Runtime versions earlier than 7.2.14: AWS : m5.2xlarge; gp2 - 100 GB For Runtime versions 7.2.14+ DE and DE Spark3: AWS: r5d.2xlarge - (ephemeral volumes) DE HA: AWS: r5d.4xlarge - (ephemeral volumes) note Compute nodes run YARN and require storage only for temporary data - this requirement is fulfilled by instance storage, so making the attached volumes count to 0 by default is more cost-efficient.
Gateway	The gateway host group can optionally be used for connecting to the cluster endpoints like Oozie, Beeline etc. This nodegroup does not run any critical services. This nodegroup resides in the same subnet as the rest of the nodegroups. If additional software binaries are required they could be installed using recipes.	0+ AWS : m5.2xlarge; gp2 - 100 GB

Service configurations
Master host group CM, HDFS, Hive (on Tez), HMS, Yarn RM, Oozie, Hue, DAS, Zookeeper, Livy, Zeppelin and Sqoop	Gateway host group Configurations for the services on the master node	Worker host group Data Node and YARN NodeManager	Compute group YARN NodeManager

Configurations

Note the following:

There is a Hive Metastore Service (HMS) running in the cluster that talks to the same database instance as the Data Lake in the environment.
If you use CLI to create the cluster, you can optionally pass an argument to create an external database for the cluster use such as CM, Oozie, Hue, and DAS. This database is by default embedded in the master node external volume. If you specify the external database to be of type HA or NON_HA, the database will be provisioned in the cloud provider. For all these types of databases the lifecycle is still associated with the cluster, so upon deletion of the cluster, the database will also be deleted.
The HDFS in this cluster is for storing the intermediary processing data. For resiliency, store the data in the cloud object stores.
For high availability requirements choose the Data Engineering High Availability cluster shape.

Architecture of the Data Engineering HA for AWS cluster

The Data Engineering HA for AWS and Azure cluster shape provides failure resilience for several of the Data Engineering HA services, including Knox, Oozie, HDFS, HS2, Hue, Livy, YARN, and HMS.

Services that do not yet run in HA mode include Cloudera Manager, DAS, and Zeppelin.

The architecture outlined in the diagram above handles the failure of one node in all of the host groups except for the “masterx” group. See the table below for additional details about the component interactions in failure mode:


Component	Failure	User experience
Knox	One of the Knox services is down	External users will still be able to access all of the UIs, APIs, and JDBC.
Cloudera Manager	The first node in manager host group is down	The cluster operations (such as repair, scaling, and upgrade) will not work.
Cloudera Manager	The second node in the manager host group is down	No impact.
HMS	One of the HMS services is down	No impact.
Hue	One of the Hue services is down in master host group	No impact.
HS2	One of the HS2 services is down in the master host group	External users will still be able to access the Hive service via JDBC. But if Hue was accessing that particular service it will not failover to the other host. The quick fix for Hue is to restart Hue to be able to use Hive functionality.
YARN	One of the YARN services is down	No impact.
HDFS	One of the HDFS services is down	No impact.
Nginx	Nginx in one of the manager hosts is down	Fifty percent of the UI, API, and JDBC calls will be affected. If the entire manager node is down, there is no impact. This is caused by the process of forwarding and health checking that is done by the network load-balancer.
Oozie	One of the Oozie servers is down in the manager host group.	No impact for AWS and Azure as of Cloudera Runtime version 7.2.11. If you create a custom template for DE HA, follow these two rules: Oozie must be in single hostgroup. Oozie and Hue must not be in the same hostgroup.

Custom templates

Any custom DE HA template that you create must be forked from the default templates of the corresponding version. You must create a custom cluster definition for this with the JSON parameter “enableLoadBalancers”: true , using the create-aws/azure/gcp-cluster CLI command parameter --request-template. Support for pre-existing custom cluster definitions will be added in a future release. As with the template, the custom cluster definition must be forked from the default cluster definition. You are allowed to modify the instance types and disks in the custom cluster definition. You must not change the placement of the services like Cloudera Manager, Oozie, and Hue. Currently the custom template is fully supported only via CLI.

The simplest way to change the DE HA definition is to create a custom cluster definition. In the Create Data Hub UI when you click Advanced Options, the default definition is not used fully, which will cause issues in the HA setup.