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.
6.2 Administration
This section describes how to manage the nodes and services that make up a cluster.
- Administering Users and Clusters
  Lists topics that help manage a data-fabric cluster.
- Administering Nodes
  Provides a synopsis of managing nodes in a cluster.
  - Managing Nodes
    Describes the Nodes page on the Control System.
  - Managing Roles
    Describes how to manage roles on a node.
  - Managing Services
    Synopsis on managing services.
  - Managing Disks
    Provides a brief overview of adding and removing disks from the HPE Ezmeral Data Fabric file system.
    - Viewing the List of Disks
      Explains how to view the disks on a node using either the Control System or the CLI.
    - Setting Up Disks for HPE Ezmeral Data Fabric
      This section describes how to set up disks during the normal installation process. Go to the ReferenceGuide/disksetup.html command page for information about other uses of this command.
    - Adding Disks to file system
      Describes how to add disks using either the Control System or the CLI.
    - Removing Disks from the File System
      Explains how to remove disks using either the Control System or the CLI.
    - Determining the Amount of Free Disk From the Command-Line
      Lists the command to display the amount of free disk space.
    - Tolerating Slow Disks
      Explains how to tune disk response timeouts.
    - Formatting Disks on a Node From the Command-line
      Provides an overview of the disksetup script to format disks from the command line.
    - Handling Disk Failures
      Explains how to handle disk failures.
      - Examining the Cause of Failure
        Names the log file that contains the cause of disk failures.
      - Recovering from Disk Failure
        Lists the disk errors and their resolution.
      - Addressing Data Alarms
        Lists all the data alarms and their mitigation.
      - Removing and Replacing Disks
    - Designating NICs for HPE Ezmeral Data Fabric
      Explains how to assign IP address blocks for HPE Ezmeral Data Fabric.
    - Working with a Logical Volume Manager
      Explains the role and usage of a Logical Volume Manager.
    - Tuning for SSDs
      Lists the parameters to tune for optimal SSD performance.
- Administering Volumes
  This section provide information about how to organize and manage data using volumes, a unique feature of HPE Ezmeral Data Fabric clusters.
- Administering Files and Directories
- Administering Tables
  Administration of the HPE Ezmeral Data Fabric Database is done primarily via the command line (maprcli) or with the Managed Control System (MCS). Regardless of whether the HPE Ezmeral Data Fabric Database table is used for binary files or JSON documents, the same types of commands are used with slightly different parameter options. HPE Ezmeral Data Fabric Database administration is associated with tables, columns and column families, and table regions.
- Administering Streams
- Administering Data Fabric Gateways
  A HPE Ezmeral Data Fabric gateway mediates one-way communication between a source HPE Ezmeral Data Fabric cluster and a destination cluster. You can replicate HPE Ezmeral Data Fabric Database tables (binary and JSON) and HPE Ezmeral Data Fabric Streams streams. HPE Ezmeral Data Fabric gateways also apply updates from JSON tables to their secondary indexes and propagate Change Data Capture (CDC) logs.
- Administering Services
- Monitoring the Cluster
  This section describes how to monitor the health and performance of a MapR cluster.
- Configuring Security
  Describes how to configure security and manage secure clusters.
- Managing Secure Clusters
  Provides procedures that will enable you to use MapR clusters securely.
- Administering the Data Access Gateway
  The HPE Ezmeral Data Fabric Data Access Gateway is a service that acts as a proxy and gateway for translating requests between lightweight client applications and the HPE Ezmeral Data Fabric cluster. This section describes considerations when upgrading the service, how to modify configuration settings, and how to administer and manage the service.
- Planning for High Availability
- Administrator's Reference
  This section contains in-depth reference information for the administrator.
- Troubleshooting Cluster Administration
  Lists the common errors and their solutions.
- Best Practices for Backing Up HPE Ezmeral Data Fabric Information
  Lists the best practices and performance considerations to follow when backing up HPE Ezmeral Data Fabric information.
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.

Handling Disk Failures

Explains how to handle disk failures.

When a disk fails, data-fabric raises the node-level alarm NODE_ALARM_DISK_FAILURE on the node with the failed disk (or disks). At the same time, other disks in the same storage pool as the failed disk are taken offline. You can look at the Control System Overview page to view the health of the nodes and a list of alarms.

When you see a disk failure alarm, examine the log file at /opt/mapr/logs/faileddisk.log and check the Failure Reason field.