Containers

How to run Cassandra 4 with Docker and Docker-Compose

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In this guide we are going to explore how to run Cassandra locally with docker and docker compose. This can be helpful if you want to run Cassandra locally without installing it in your server or if you want to run multiple versions of Cassandra seamlessly.

Also check:

Prerequisites

To follow along, ensure you have the following:

  1. Docker installed locally and permissions to use it to launch containers
  2. Docker compose is installed locally
  3. Basic knowledge of the command line

Table of content

  1. Using the docker run command
  2. Using the docker-compose tool

1. Using the docker run command

We are going to use the docker run command to achieve our goal. The version of Cassandra that we want is cassandra:4.0 – the latest version of cassandra.

➜ docker run -d \
    --name my-cassandra \
    -p 9042:9042 \
    -v ~/apps/cassandra:/var/lib/cassandra \
    -e CASSANDRA_CLUSTER_NAME=citizix \
    cassandra:4.0
Unable to find image 'cassandra:4.0' locally
4.0: Pulling from library/cassandra
7b1a6ab2e44d: Pull complete
237daeb1ae28: Pull complete
5525469b77d0: Pull complete
3d55dee44697: Pull complete
e9433e47fbec: Pull complete
2b83006bed25: Pull complete
e6aac180715e: Pull complete
7743412d1917: Pull complete
4b91229d79d5: Pull complete
Digest: sha256:cf6ae1b3e6253c9cde91dbde6dad1d6c0314939e0f9e18253c6308482e505728
Status: Downloaded newer image for cassandra:4.0
6071e47c57f7b90d58a03ede26ce2eee220298108fd12d356525694363db4c80

In the above command:

  • The -d instructs docker container to run as a detached process. It run container in background and print container ID
  • -p is for port mapping. We are instructing the container to expose the container port externally. Container port 9042 is mapped to host port9042. That means the service can be accessed through localhost:9042
  • The -v directive is used to mount volumes. In our case we are mounting the container volume /var/lib/cassandra to host path ~/apps/cassandra. Containers are ephemeral devices that will contain its data for the time it is running. Once a container is stopped, its data is lost. Mounting volumes ensures that the data is added to a host path that can be reused when the container is restarted.
  • The -e argument is for the environment variables. The supplied environment variables will be used to set up cassandra cluster name.

To check that our container is running as expected, use the docker ps command:

➜ docker ps
CONTAINER ID   IMAGE           COMMAND                  CREATED          STATUS          PORTS                                                                          NAMES
6071e47c57f7   cassandra:4.0   "docker-entrypoint.s…"   50 seconds ago   Up 47 seconds   7000-7001/tcp, 7199/tcp, 9160/tcp, 0.0.0.0:9042->9042/tcp, :::9042->9042/tcp   my-cassandra

In my case the container is running as my-cassandra the name we gave it. We can login to the container using the docker exec command while executing /bin/bash interactively. Here we are also logging in to posgtres with the credentials we specified above and checking the version.

➜ docker exec -it my-cassandra /bin/sh
# cqlsh -u cassandra -p cassandra
Connected to citizix at 127.0.0.1:9042
[cqlsh 6.0.0 | Cassandra 4.0.1 | CQL spec 3.4.5 | Native protocol v5]
Use HELP for help.
[email protected]>
[email protected]> show version
[cqlsh 6.0.0 | Cassandra 4.0.1 | CQL spec 3.4.5 | Native protocol v5]
[email protected]> describe keyspaces

system       system_distributed  system_traces  system_virtual_schema
system_auth  system_schema       system_views

[email protected]>

If you need to clean up the container when not in use, you can stop and remove the container using this command:

docker stop my-cassandra

# Removing
docker rm my-cassandra

2. Using the docker-compose tool

We can achieve the same functionality with docker-composeDocker Compose is a tool for defining and running multi-container Docker applications. With Compose, you use a YAML file to configure your application’s services.

Docker Compose allows you to define the service (Cassandra in our case) with properties like the image to use, ports to expose, volumes to mount and environment variables.

Here is how we would use docker-compose to achieve the functionality above. Save this as docker-compose.yaml:

version: '3.9'

services:
  cassandra:
    image: cassandra:4.0
    ports:
      - 9042:9042
    volumes:
      - ~/apps/cassandra:/var/lib/cassandra
    environment:
      - CASSANDRA_CLUSTER_NAME=citizix

Now bring up the containers:

➜ docker-compose up -d
Starting tmp_cassandra_1 ... done

The commands:

  • up brings up the container
  • -d in a detached mode

Verify the container processes using the ps command:

➜ docker-compose ps
     Name                    Command               State                                        Ports
-------------------------------------------------------------------------------------------------------------------------------------------
tmp_cassandra_1   docker-entrypoint.sh cassa ...   Up      7000/tcp, 7001/tcp, 7199/tcp, 0.0.0.0:9042->9042/tcp,:::9042->9042/tcp, 9160/tcp

To login to the container and login to Cassandra, use this:

➜ docker-compose exec cassandra /bin/bash
[email protected]:/# cqlsh -u cassandra -p cassandra
Connected to citizix at 127.0.0.1:9042
[cqlsh 6.0.0 | Cassandra 4.0.1 | CQL spec 3.4.5 | Native protocol v5]
Use HELP for help.
[email protected]> show version
[cqlsh 6.0.0 | Cassandra 4.0.1 | CQL spec 3.4.5 | Native protocol v5]
[email protected]> describe keyspaces

system       system_distributed  system_traces  system_virtual_schema
system_auth  system_schema       system_views

[email protected]>

Conclusion

In this guide we managed to run Cassandra 4 as a container in our system, we explored using the docker run command while passing the required arguments an alternative approach of simplifying the process with docker-compose

I am a Devops Engineer, but I would describe myself as a Tech Enthusiast who is a fan of Open Source, Linux, Automations, Cloud and Virtualization. I love learning and exploring new things so I blog in my free time about Devops related stuff, Linux, Automations and Open Source software. I can also code in Python and Golang.

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