Installing DataStax Enterprise 5.1 on RHEL-based systems using Yum

Use these instructions for installing DataStax Enterprise (DSE) 5.1 on RHEL-based systems using Yum.

Some things to know about installing DSE

When installed with Yum, DataStax Enterprise runs as a service. The service initialization script is located in /etc/init.d/dse. Run levels are not set by the package.
This procedure installs DataStax Enterprise 5.1 and the DataStax Agent. It does not install OpsCenter, Studio, or Graph Loader.

If using OpsCenter 6.0, override the default DataStax Agent. However, OpsCenter 6.8 is recommended. See DSE product compatibility.

sudo yum install dse-full datastax-agent-6.0.supported_version-1 #during installation

sudo yum install datastax-agent-6.0.supported_version-1 #after installation

SECURITY RISK

When DSE is installed, it creates a superuser called cassandra in the database and runs as this user. It also creates this same superuser in the operating system. Do not use the cassandra superuser in production. Using the cassandra superuser is a security risk. See Adding a superuser login.

For more information about managing Java, see Managing Java installs.

Prerequisites

Root or sudo access.
A supported platform.
Yum Package Management application.
Configure your operating system to use the latest version of Java 8:
- Recommended. The latest build of a TCK (Technology Compatibility Kit) Certified OpenJDK version 8. For example, OpenJDK 8 (1.8.0_151 minimum). DataStax’s recommendation changed due to the end of public updates for Oracle JRE/JDK 8. See Oracle Java SE Support Roadmap.
- Supported. Oracle Java SE 8 (JRE or JDK) (1.8.0_151 minimum)
RedHat-compatible distributions require EPEL (Extra Packages for Enterprise Linux).
Python 3.6 through 3.11, or Python 2.7.x. Each listed version provides support for cqlsh, but DataStax recommends using Python 3.11.
Install Python 2.7 on older RHEL-based package installations
If you have an older distribution, such as CentOS 6.5, you must install Python 2.7:
1. Verify your Python version:
  
  python -V
2. If the result isn’t Python version 2.7.x, install it from the Software Collections (SCL) Repository by running the following commands:
  
  sudo yum update
  
  sudo yum install scl-utils
  
  sudo yum install centos-release-scl-rh
  
  sudo yum install python27
  
  sudo scl enable python27 bash
3. Verify the update by checking the Python version again. Make sure the result is Python 2.7.x.
4. After logging out or restarting, you must enable python 2.7:
  
  sudo scl enable python27 bash
  
  Note that enabling Python 2.7 in .bash_profile or .bashrc causes the machine to hang because CentOS 6 relies on Python 2.6 for Yum.

Hardware requirements

See Recommended production settings.

Procedure

In a terminal window:

Verify that a required version of Java is installed:

java -version

DataStax recommends the latest build of a Technology Compatibility Kit (TCK) Certified OpenJDK version 8.

If OpenJDK, the results should look like:

openjdk version "1.8.0_171"
OpenJDK Runtime Environment (build 1.8.0_171-8u171-b11-0ubuntu0.16.04.1-b11)
OpenJDK 64-Bit Server VM (build 25.171-b11, mixed mode)

If Oracle Java, the results should look like:

java version "1.8.0_181"
Java(TM) SE Runtime Environment (build 1.8.0_181-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.181-b13, mixed mode)

If not OpenJDK 8 or Oracle Java 8, see Install the Java Virtual Machine.

Add the DataStax Yum repository to a file called /etc/yum.repos.d/datastax.repo:

Set the gpgcheck=1 to perform a GPG signature check.
```
[datastax]
name=DataStax Repo for DataStax Enterprise
baseurl=https://rpm.datastax.com/enterprise
enabled=1
gpgcheck=0
```
If you have enabled signature verification (gpgcheck=1), import the DataStax Enterprise repository key:
```
sudo rpm --import https://rpm.datastax.com/rpm/repo_key
```

Install the DataStax Enterprise packages:

Specify all packages; otherwise, the installation fails.

Install any 5.1.x version:

To view the available versions, see the Release notes.

sudo yum install dse-5.1.version_number-1 \
    dse-full-5.1.version_number-1 \
    dse-libgraph-5.1.version_number-1 \
    dse-libcassandra-5.1.version_number-1 \
    dse-libhadoop2-client-5.1.version_number-1 \
    dse-libsolr-5.1.version_number-1 \
    dse-libtomcat-5.1.version_number-1 \
    dse-liblog4j-5.1.version_number-1 \
    dse-libspark-5.1.version_number-1

For example:

sudo yum install dse-5.1-1 \
    dse-full-5.1-1 \
    dse-libgraph-5.1-1 \
    dse-libcassandra-5.1-1 \
    dse-libhadoop2-client-5.1-1 \
    dse-libsolr-5.11 \
    dse-libtomcat-5.1-1 \
    dse-liblog4j-5.1-1 \
    dse-libspark-5.1-1

Optional: Install the demos:

Installing the DSE demos is not recommended for production. Only install the demos in development environments to run tutorials.
```
sudo yum install dse-demos-version_number-1
```

Result

DataStax Enterprise is ready for additional configuration:

For production, be sure to change the cassandra user. Failing to do so is a security risk. See Creating superuser accounts.
DataStax Enterprise provides several types of workloads (default is transactional). See startup options for service or stand-alone installations.
The Next steps section below provides links to related tasks and information.

Optional: Configure systemd units: RedHat systemd configuration.

Optional: Single-node cluster installations only:

If DataStax Enterprise is not already running:
```
sudo service dse start
```
For more start options, see Starting DataStax Enterprise as a service.

Verify that DataStax Enterprise is running:

nodetool status

Results using vnodes:

Datacenter: Cassandra
=====================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
--  Address    Load       Tokens  Owns    Host ID                               Rack
UN  127.0.0.1  82.43 KB   128     ?       40725dc8-7843-43ae-9c98-7c532b1f517e  rack1

Results not using vnodes:

Datacenter: Analytics
=====================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
--  Address         Load       Owns    Host ID                               Token                 Rack
UN  172.16.222.136  103.24 KB  ?       3c1d0657-0990-4f78-a3c0-3e0c37fc3a06  1647352612226902707   rack1

If your OpsCenter version is not compatible with DSE 5.1, upgrade OpsCenter to a compatible version.

Next steps

You must change or delete the cassandra user created on installation. See Creating superuser accounts.
Configure startup options: service | stand-alone.
Configuring DataStax Enterprise - Settings for DSE Advanced Security, In-Memory, DSE Advanced Replication, DSE Multi-Instance, DSE Tiered Storage, and more.
Configuration and log file locations - Services and package installations.
Configuration and log file locations - No Services and tarball installations.
Changing logging locations after installation.
Starting and stopping DataStax Enterprise.
Preparing DataStax Enterprise for production.
Recommended production settings.
Capacity planning and hardware selection for DataStax Enterprise implementations.
Configuring the heap dump directory to avoid server crashes.
DataStax Studio documentation.