How to Install and Configure Cassandra

How to Install and Configure Cassandra

Apache Cassandra is a distributed NoSQL database designed for handling massive amounts of data across many Breeze instances with no single point of failure. It provides linear scalability, tunable consistency, and excels at write-heavy workloads such as event logging, IoT data, and messaging systems.

Installing Cassandra

On your Breeze instance running Ubuntu, add the Apache Cassandra repository and install:

sudo apt install -y apt-transport-https gnupg
curl -fsSL https://downloads.apache.org/cassandra/KEYS | sudo gpg --dearmor -o /usr/share/keyrings/cassandra.gpg
echo "deb [signed-by=/usr/share/keyrings/cassandra.gpg] https://debian.cassandra.apache.org 50x main" | \
  sudo tee /etc/apt/sources.list.d/cassandra.list
sudo apt update
sudo apt install -y cassandra

Single-Node Configuration

For development on a single Breeze instance, the default configuration works. Edit /etc/cassandra/cassandra.yaml to verify these settings:

cluster_name: 'BreezeCluster'
listen_address: localhost
rpc_address: localhost
seed_provider:
  - class_name: org.apache.cassandra.locator.SimpleSeedProvider
    parameters:
      - seeds: "127.0.0.1"
endpoint_snitch: SimpleSnitch
data_file_directories:
  - /var/lib/cassandra/data
commitlog_directory: /var/lib/cassandra/commitlog

Multi-Node Cluster Setup

For a production cluster across multiple Breeze instances, configure each node with its own IP and designate seed nodes:

cluster_name: 'BreezeCluster'
num_tokens: 256
listen_address: this-breeze-ip
rpc_address: 0.0.0.0
broadcast_rpc_address: this-breeze-ip
seed_provider:
  - class_name: org.apache.cassandra.locator.SimpleSeedProvider
    parameters:
      - seeds: "breeze1-ip,breeze2-ip"
endpoint_snitch: GossipingPropertyFileSnitch
auto_bootstrap: true

Start Cassandra on each node:

sudo systemctl enable cassandra
sudo systemctl start cassandra

Check the cluster status:

nodetool status

All nodes should show UN (Up Normal).

Creating a Keyspace and Table

Connect with the CQL shell and create a keyspace with the appropriate replication strategy:

cqlsh

CREATE KEYSPACE myapp WITH replication = {
  'class': 'NetworkTopologyStrategy',
  'datacenter1': 3
};

USE myapp;

CREATE TABLE events (
    event_id UUID,
    user_id UUID,
    event_type TEXT,
    event_time TIMESTAMP,
    payload TEXT,
    PRIMARY KEY ((user_id), event_time, event_id)
) WITH CLUSTERING ORDER BY (event_time DESC)
  AND default_time_to_live = 7776000;  -- 90 days TTL

The partition key (user_id) distributes data evenly, and the clustering key (event_time DESC) orders events within each partition for efficient time-range queries.

Memory and Performance Tuning

Edit /etc/cassandra/jvm-server.options to set the heap size based on your Breeze instance resources:

-Xms4G
-Xmx4G
-Xmn800M

Set heap to no more than 50% of available RAM, with a maximum of 8 GB. For Breeze instances with 8 GB RAM, use 4 GB heap. Also adjust concurrent_reads and concurrent_writes in cassandra.yaml based on your CPU core count (typically 16 times the number of cores for reads, 8 times for writes).

Monitoring with nodetool

Key monitoring commands:

nodetool status          # Cluster overview
nodetool info            # Node-level details
nodetool tpstats         # Thread pool statistics
nodetool cfstats myapp   # Table-level statistics
nodetool compactionstats # Active compactions

Regular compaction and repair operations keep your Cassandra cluster healthy across your Breeze instances. Schedule repairs with nodetool repair weekly during off-peak hours.