Install Apache Cassandra on Ubuntu

What you need

• Ubuntu 22.04 LTS (other versions are similar).
• Root or sudo rights.
• Java. Cassandra needs OpenJDK 11 (for Cassandra 4.x). Cassandra 5.x supports Java 11 and 17.

Step 1: Install Java

sudo apt update
sudo apt-get install openjdk-11-jdk

Check it:

java -version

Step 2: Add the Cassandra repository and key

Import the key into a keyring:

curl -fsSL https://downloads.apache.org/cassandra/KEYS | sudo gpg --dearmor -o /etc/apt/keyrings/apache-cassandra.gpg

Add the repository (use 41x for Cassandra 4.1, or the series you want):

echo "deb [signed-by=/etc/apt/keyrings/apache-cassandra.gpg] https://debian.cassandra.apache.org 41x main" | sudo tee /etc/apt/sources.list.d/cassandra.sources.list

Step 3: Install Cassandra

sudo apt update
sudo apt install cassandra

Step 4: Start the service

sudo systemctl enable cassandra
sudo systemctl start cassandra

Step 5: Check it

sudo systemctl status cassandra

Use nodetool to see the node:

nodetool status

UN in the output means the node is Up and Normal. The first start can take a minute or two.

Configure Cassandra

The main file is /etc/cassandra/cassandra.yaml. Important settings:

• cluster_name. The name of the cluster. All nodes must use the same name.
• listen_address and rpc_address. The addresses that Cassandra uses for other nodes and for clients.
• seed_provider. The IP addresses of the seed nodes.
• data_file_directories. Where the data is stored.

Restart after a change:

sudo systemctl restart cassandra

Use the shell

cqlsh

Then create a keyspace:

CREATE KEYSPACE test WITH replication = {'class': 'SimpleStrategy', 'replication_factor': 1};

Firewall

Open port 9042 (clients) and 7000 (nodes) only where needed.

Quick recap

• Install Java, add the repository, install cassandra.
• Check with nodetool status.
• Edit cassandra.yaml for cluster settings.