If you want to deploy a database capable of handling massive amounts of unstructured data, Apache Cassandra might do the trick. Jack Wallen shows you how to deploy this NoSQL database on AlmaLinux.

Image: Cassandra

Apache Cassandra is a very powerful NoSQL database that is perfectly at home driving big data. This particular database provides linear scalability, high availability and serious performance. With Apache Cassandra, your business can process large volumes of fast-moving data reliably.

SEE: Hiring Kit: Database engineer (TechRepublic Premium)

If businesses like Facebook, Instagram and Netflix can depend on Apache Cassandra, I’m betting your company could as well.

Let me walk you through the process of installing Apache Cassandra. I’ll be demonstrating on AlmaLinux 8 which can be deployed on bare metal in your data center or via a third-party cloud host (such as Google Cloud, AWS and Azure).

What you’ll need

The only things you’ll need to get Apache Cassandra up and running are an instance of AlmaLinux and a user with sudo privileges. That’s it … let’s make this happen.

How to install the necessary dependencies

The first thing we’ll do is install the necessary dependencies for Apache Cassandra. Log into your AlmaLinux server and update dnf with the command:

sudo dnf update

Once that completes, install the next set of dependencies with:

sudo dnf install yum-utils epel-release -y

After those two package installations are complete, enable PowerTools (so we can install the necessary Java package) with:

sudo dnf config-manager --set-enabled powertools

Install OpenJDK with:

sudo dnf install java-11-openjdk -y

If you find Java 11 causes problems with your installation (I’ve had this happen on a couple of occasions), opt for a Java 8 installation with:

sudo dnf install java-1.8.0-openjdk -y

How to create the Apache Cassandra repository file

Next, we’ll create the Apache Cassandra repository file with:

sudo nano /etc/yum.repos.d/cassandra.repo

In that file, paste the following content:

[cassandra]
name=Apache Cassandra
baseurl=https://downloads.apache.org/cassandra/redhat/40x/
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://downloads.apache.org/cassandra/KEYS

Save and close the file.

Update dnf with:

sudo dnf update -y

How to install Apache Cassandra

We can now install Apache Cassandra with the command:

sudo dnf install cassandra -y

After the installation completes, start and enable the service with:

sudo systemctl start cassandra
sudo systemctl enable cassandra

It will take a minute or so for the Cassandra node to appear. Check the status with:

nodetool status

In the output, you should see something like that shown in Figure A.

Figure A

Our Apache Cassandra service is up and running.
Our Apache Cassandra service is up and running.

You can then access the Apache Cassandra console with the command:

cqlsh

By default, the cluster name will be something like Test Cluster. To rename the cluster issue the command (in the Apache Cassandra console):

UPDATE system.local SET cluster_name="NAME" WHERE KEY = 'local';

Where NAME is the new name for the cluster. Exit the console with the exit command and then log back in to see the new name listed (Figure B).

Figure B

I've renamed my Apache Cassandra cluster "Hive."
I’ve renamed my Apache Cassandra cluster “Hive.”

That will only be temporary. When the service restarts, the name will revert to Test Cluster. To make that change permanent, open the configuration file with:

sudo nano /etc/cassandra/default.conf/cassandra.yaml

Look for the line:

cluster_name: 'Test Cluster'

Change Test Cluster to whatever you want to name your Apache Cassandra cluster. Save and close the file. Flush the cache and restart Apache Cassandra with the following commands:

nodetool flush system
sudo sytemctl restart cassandra

Now, when the service (or the server) restarts, the name will stick. Remember, however, that after restarting the service, it can take some time for it to come back up.

Congratulations, you now have the Apache Cassandra NoSQL database server up and running and are ready to start building databases like a pro.

Subscribe to TechRepublic’s How To Make Tech Work on YouTube for all the latest tech advice for business pros from Jack Wallen.



Source link