MapR Prerequisites

MapR is now HPE Ezmeral Data Fabric. At times, this documentation uses "MapR" to refer to both MapR and HPE Ezmeral Data Fabric. For information about supported versions, see Supported Systems and Versions.

Due to licensing restrictions, StreamSets cannot distribute MapR libraries with Data Collector. As a result, you must perform additional steps to enable the Data Collector machine to connect to MapR. Data Collector does not display MapR stages in stage library lists nor the MapR Streams statistics aggregator in the pipeline properties until you perform these prerequisites. Install Data Collector on a node in the MapR cluster or on a client machine.

The MapR prerequisites include installing all necessary client libraries on the Data Collector machine. If you use a core installation of Data Collector, you must install the MapR stage libraries. If you use a common installation of Data Collector, you install MapR stage libraries when Data Collector does not include the version that you want to use. Then, you run the command to set up MapR.

If the MapR cluster is enabled with built-in security, you also must configure Data Collector to connect to a secure MapR cluster and ensure that a valid ticket exists for the Data Collector user.

Supported Versions

This release supports the following MapR versions:

MapR 6.0.0 with optional EEP 4.x
MapR 6.0.1 with optional EEP 5.x
MapR 6.1.x with optional EEP 6.x
HPE Ezmeral Data Fabric 7.0.x with optional EEP 8.x

Different MapR and HPE Ezmeral Data Fabric versions require different versions of Java. For more information, see Java Versions and Available Features.

To view the complete list of supported EEPs, see the HPE Ezmeral Data Fabric documentation.

Step 1. Install Client Libraries as Needed

You can install Data Collector on a node in the MapR cluster or on a client machine. A client machine is one that is outside the cluster or on your local machine. When you install Data Collector on a client machine, the MapR client package must be installed on the machine.

If you install Data Collector on a node in the MapR cluster, or on a client machine that has the MapR client package installed, you can skip this step.

If the MapR client package is not installed on a client machine, download and install the following files:

MapR client library - Typically named mapr-client_<version>.<ext>.
You can download the files for your operating system here:
```
http://archive.mapr.com/releases/
```
Kafka client library - Typically named mapr-kafka-<version>.<ext>.
You can download the files for your operating system here:
```
http://package.mapr.com/releases/MEP/
```

Note: If you encounter an error when you run a MapR pipeline that indicates that Data Collector cannot find the MapR client, configure the environment to enable Data Collector to use the MapR libraries. For example, on Linux, you might use

export
                    LD_LIBRARY_PATH="${MAPR_HOME}/lib"

. On MacOS, you might use export JAVA_LIBRARY_PATH="${MAPR_HOME}/lib".

Step 2. Install MapR Stage Libraries

Install MapR stage libraries if you use a core installation of Data Collector, which does not include MapR stage libraries.

If you use a common installation of Data Collector and you need a different MapR version that is not included with the installation, you must also install MapR stage libraries. If you use a full installation of Data Collector or if you use Data Collector on a cloud service provider, your Data Collector installation includes all stage libraries, so you can skip this step.

When installing MapR stage libraries, you must install both the MapR stage library and the Ecosystem Pack (EEP) stage library for your supported version of MapR. For example, if using HPE Ezmeral Data Fabric version 7.0.x, you must install both of the following stage libraries:

streamsets-datacollector-mapr_7_0-lib
streamsets-datacollector-mapr_7_0-mep8-lib

For more information about installing additional stage libraries, see Install Additional Stage Libraries.

Step 3. Run the Command to Set Up MapR

After you install all required MapR client libraries and install MapR stage libraries, run the setup-mapr command on every Data Collector machine. This command modifies configuration files and creates the required symbolic links to enable Data Collector to work with MapR. You can run the command in interactive or non-interactive mode.

In interactive mode, the command prompts you for the MapR version and home directory. In non-interactive mode, you define the MapR version and home directory in environment variables before running the command.

In both modes, the command checks if the MapR distribution of Spark is installed in the specified MapR cluster. If a supported version is installed, the command also installs the MapR Spark stage library for you.

Running the Command in Interactive Mode

When you run the setup-mapr command in interactive mode, the command prompts you for the MapR version and home directory.

Set the following environment variables:


Environment Variable	Description
SDC_HOME	Data Collector home directory. Note: The default home directory for an RPM installation is `/opt/streamsets-datacollector`. The tarball home directory is the location where you extracted the file.
SDC_CONF	Data Collector configuration directory.
MAPR_MEP_VERSION	EEP version. Enter a single digit EEP version number: 4, 5, 6, or 8.

Use the following command to set an environment variable:

export <environment variable>=<value>

For example, use the following commands if you used the default home and configuration directories for an RPM installation, and use EEP 8:

export SDC_HOME=/opt/streamsets-datacollector
export SDC_CONF=/etc/sdc
export MAPR_MEP_VERSION=8

Use the following command from the $SDC_HOME directory to set up MapR:
```
bin/streamsets setup-mapr
```
When prompted, enter the MapR version.
Enter the full three-digit version: 6.0.0, 6.0.1, 6.1.0, or 7.0.0.
When prompted, enter the absolute path to the MapR home directory, usually /opt/mapr.
Restart Data Collector and verify that MapR stages appear in stage library lists.

Running the Command in Non-Interactive Mode

When you run the setup-mapr command in non-interactive mode, you define the MapR version and home directory in environment variables before running the command.

Set the following environment variables:


Environment Variable	Description
SDC_HOME	Data Collector home directory. Note: The default home directory for an RPM installation is `/opt/streamsets-datacollector`. The tarball home directory is the location where you extracted the file.
SDC_CONF	Data Collector configuration directory.
MAPR_HOME	MapR home directory, usually /opt/mapr.
MAPR_VERSION	MapR version. Enter the full three-digit version: 6.0.0, 6.0.1, 6.1.0, or 7.0.0.
MAPR_MEP_VERSION	EEP version. Enter a single digit EEP version number: 4, 5, 6, or 8.

Use the following command to set an environment variable:

export <environment variable>=<value>

For example, use the following commands if you used the default home and configuration directories for an RPM installation, the default MapR home directory, MapR 7.0.0, and EEP 8:

export SDC_HOME=/opt/streamsets-datacollector
export SDC_CONF=/etc/sdc
export MAPR_HOME=/opt/mapr
export MAPR_VERSION=7.0.0
export MAPR_MEP_VERSION=8

Use the following command from the $SDC_HOME directory to set up MapR:
```
bin/streamsets setup-mapr
```
Restart Data Collector and verify that MapR stages appear in stage library lists.

Step 4. Configure Data Collector for Secure MapR Clusters

When a MapR cluster has built-in security enabled, you must configure Data Collector to connect to a secure MapR cluster.

Modify the SDC_JAVA_OPTS environment variable to add the -Dmaprlogin.password.enabled configuration property.

Modify the environment variable in the required file based on how you start Data Collector. For more information about the required file to edit, see Modifying Environment Variables.

Manual start - Uncomment the following line in the sdc-env.sh file:

#export SDC_JAVA_OPTS="${SDC_JAVA_OPTS} -Dmaprlogin.password.enabled=true"

Service start on operating systems that use the SysV init system - On CentOS 6, Oracle Linux 6, Red Hat Enterprise Linux 6, or Ubuntu 14.04 LTS, uncomment the following line in the sdcd-env.sh file:
```
#export SDC_JAVA_OPTS="${SDC_JAVA_OPTS} -Dmaprlogin.password.enabled=true"
```
Service start on operating systems that use the systemd init system - On CentOS 7, Oracle Linux 7, Red Hat Enterprise Linux 7, or Ubuntu 16.04 LTS, add the following line to the file that overrides the default settings in the sdc.service file:
```
Environment=SDC_JAVA_OPTS=-Dmaprlogin.password.enabled=true
```
Override the default values in the sdc.service file using the same procedure that you use to override unit configuration files on a systemd init system. For an example, see "Example 2. Overriding vendor settings" in this systemd.unit manpage.
After overriding the default values, use the following command to reload the systemd manager configuration:
```
systemctl daemon-reload
```

After modifying the environment variables, restart Data Collector to enable the changes.

Step 5. Run Data Collector as a MapR Ticket User

To connect to a secure MapR cluster with built-in security enabled, ensure that a valid user, tenant, or service ticket exists for the Data Collector user in MapR. To generate tickets, see the MapR documentation.

Note: If the MapR ticket that Data Collector uses allows impersonation, then you can configure MapR stages in Data Collector to use Hadoop impersonation mode.

To run MapR commands in a secure cluster, Data Collector must run as the user account granted access in the MapR ticket.

For example, if you ran the following MapR command to generate the service ticket for applications running outside of the cluster, then Data Collector must run as the myappuser user account:

maprlogin generateticket -type service -out /tmp/longlived_ticket -duration 30:0:0 -renewal 90:0:0

Configure Data Collector to run as the required user account based on how you start Data Collector:

Manual start

When Data Collector starts manually, it runs as the system user account logged into the command prompt when you use the following launch command from the $SDC_DIST directory:

bin/streamsets dc

You can start an engine for a secure MapR cluster in either of the following ways:

Log into the command prompt as the user account granted access in the MapR ticket, then use the following command from the $SDC_DIST directory:
```
bin/streamsets dc
```
Impersonate the required user account by using the following launch command from the $SDC_DIST directory, where <user> is the user account granted access in the MapR ticket:
```
sudo -u <user> bin/streamsets dc
```
For example:
```
sudo -u myappuser /opt/streamsets-datacollector-5.10.0/bin/streamsets dc
```

Service start

When Data Collector starts as a service, it runs as the system user account and group defined in environment variables. The default system user and group are named sdc. To use the default sdc system user and group, generate a new MapR user or service ticket for the sdc user account, as described in the MapR documentation.

To use another user account granted access to an existing MapR ticket, change the system user and group used by Data Collector. Set the Data Collector user environment variable to the user account granted access in the MapR ticket. Set the group environment variable to the system group that the user account belongs to.

Modify the environment variable in the file used by your operating system. For more information about the required file to edit, see Modifying Environment Variables.

Operating systems that use the SysV init system - On CentOS 6, Oracle Linux 6, Red Hat Enterprise Linux 6, or Ubuntu 14.04 LTS, modify the SDC_USER and SDC_GROUP environment variables in the sdcd-env.sh file.
Operating systems that use the systemd init system - On CentOS 7, Oracle Linux 7, Red Hat Enterprise Linux 7, or Ubuntu 16.04 LTS, override the User and Group environment variables in the sdc.service file.
Override the default values in the sdc.service file using the same procedure that you use to override unit configuration files on a systemd init system. For an example, see "Example 2. Overriding vendor settings" in this systemd.unit manpage.
After overriding the default values, use the following command to reload the systemd manager configuration:
```
systemctl daemon-reload
```
After modifying the environment variables, restart Data Collector to enable the changes.

When you change the system user, you must make that user the owner of all Data Collector directories:

$SDC_DIST
$SDC_CONF
$SDC_DATA
$SDC_LOG
$SDC_RESOURCES

For example, if you change the system user and group to myappuser, use the following command to change the owner of the configuration directory, $SDC_CONF, and all files in the directory to myappuser:myappuser:

chown -R myappuser:myappuser /etc/sdc

For more information on setting the user and group environment variables, see User and Group for Service Start.