HPE Ezmeral Data Fabric 6.2 is In Maintenance and transitions to "End of Maintenance" in June 2024. Please see the latest documentation.

About Release 6.2
This site contains documentation for HPE Ezmeral Data Fabric release 6.2 including installation, configuration, administration, and reference content, as well as content for the associated bundled ecosystem components and drivers.
6.2 Installation
This section contains information about installing and upgrading HPE Ezmeral Data Fabric software. It also contains information about how to migrate data and applications from an Apache Hadoop cluster to a HPE Ezmeral Data Fabric cluster.
6.2 Data Fabric
HPE Ezmeral Data Fabric is the industry-leading data platform for AI and analytics that solves enterprise business needs.
- HPE Ezmeral Data Fabric File Store
  HPE Ezmeral Data Fabric File Store is a distributed file system for data storage, data management, and data protection. File Store supports mounting and cluster access via NFS and FUSE-based POSIX clients (basic, platinum, or PACC) and also supports access and management via HDFS APIs.
- HPE Ezmeral Data Fabric Database
  HPE Ezmeral Data Fabric Database is an enterprise-grade, high-performance, NoSQL database management system that you can use for real-time, operational analytics.
- HPE Ezmeral Data Fabric Streams
  HPE Ezmeral Data Fabric Streams brings integrated publish and subscribe messaging to the Data Fabric Converged Data Platform.
  - Architecture
    Streams contain topics that have logical collections of messages.
  - Producers
    Producers are data-generating applications, such as sensors in automobiles or activity loggers in servers. Producers create messages with the collected data and publish the messages to HPE Ezmeral Data Fabric Streams topics, specifically, to HPE Ezmeral Data Fabric Streams topic-partitions.
  - Consumers
    Consumers are applications that you create such as analytics applications, reporting tools, or enterprise dashboards.
    - Consumer Subscriptions
      Consumers subscribe to topics. When a consumer subscribes to a topic or partition, it means that the consumer wants to receive messages from that topic or partition. A subscription is the list of the topics, specific partitions, or both to which a consumer is subscribed.
    - Consuming Messages
      Describes the process by which consumers consume messages.
    - Consumer Groups
      Group consumers together by setting the same value for the group.id configuration parameter when you start each consumer.
      - Parallelism when Consuming Messages
        For parallelism when reading messages from topics, you can create consumer groups. These groups consist of consumers that are associated with an ID that you set for each of the participating consumers with the group.id configuration parameter. The partitions in each topic to which all of the consumers are subscribed, are assigned dynamically to the consumers in round-robin fashion.
      - Saving Cursor Position
        The HPE Ezmeral Data Fabric Streams server uses cursors to keep track of the messages that consumers in consumer groups have read.
    - Consumer Failure and Recovery
      When a consumer that is not associated with a consumer-group ID recovers from failure and comes back online, it can either start reading its partitions from the earliest offsets or from the latest offset. This choice is determined by the auto.offset.reset configuration parameter.
  - Stream Replication
    You can replicate streams to other data-fabric clusters worldwide, or to other streams within a data-fabric cluster.
  - Stream Security
    The adminperm, copyperm, comsumeperm, produceperm, and topicperm security permissions protect topics in a stream from unauthorized access. In addition, data-fabric supports user impersonation.
- Kubernetes Interfaces for Data Fabric
  This section describes the Kubernetes Interfaces for Data Fabric, which include the Container Storage Interface (CSI) driver for multiple container-orchestration systems, and the FlexVolume driver for Kubernetes.
- Cluster Management
  Provides a synopsis of the various cluster components and their management.
- Performance
  Describes how to tune system performance, manage RDMA, and optimize CLDB tables.
- Security
  Provides an overview of the data-fabric security features.
- YARN
- Client Connections
  The following sections describe how a client connects to local and remote data-fabric clusters.
6.2 Administration
This section describes how to manage the nodes and services that make up a cluster.
6.2 Development
This section contains information related to application development for Ezmeral ecosystem components and HPE Ezmeral Data Fabric products, including the file system, Database (Key-Value and JSON), and Event Streams.
Other Docs
This section contains release-independent information, including: Installer documentation, Ecosystem release notes, interoperability matrices, security vulnerabilities, and links to other data-fabric version documentation.
Glossary
Definitions for commonly used terms in MapR Converged Data Platform environments.

Consumer Groups

Group consumers together by setting the same value for the group.id configuration parameter when you start each consumer.

For example, if you create three consumers and give each of them the group ID clickstream_consumers, together these consumers form the consumer group clickstream_consumers. HPE Ezmeral Data Fabric Streams does not generate IDs for consumer groups. You can create IDs that make sense for your purposes. You specify the group ID by using the group.id configuration parameter when you create a consumer. IDs are strings that can be up to 2457 bytes long.

You can even create a consumer group that consists of only one consumer. In such a case, the unique ID that identifies the group would be shared with no other consumers.

The following are the benefits to creating consumer groups: