version: '3'
services:
    # Configuration for the seed node DC1N1
    # The name could stand for datacenter 1, node 1
DC1N1:
        image: cassandra:3.10
        command: bash -c 'if [ -z "$$(ls -A /var/lib/cassandra/)" ] ; then sleep 0; fi && /docker-entrypoint.sh cassandra -f'
        # Network for communication between nodes
        networks:
            - dc1ring
        # Mapped the volume to a local directory.
        volumes:
            - ./n1data:/var/lib/cassandra
        # Environment variable for the Cassandra configuration.
        # CASSANDRA_CLUSTER_NAME must be identical on all nodes.
        environment:
            - CASSANDRA_CLUSTER_NAME=Test Cluster
            - CASSANDRA_SEEDS=DC1N1
        # Expose ports for cluster communication
        expose:
            # Intra-node communication
            - 7000
            # TLS intra-node communication
            - 7001
            # JMX
            - 7199
            # CQL
            - 9042
            # Thrift service
            - 9160
            # recommended Cassandra Ulimit settings
        ulimits:
            memlock: -1
            nproc: 32768
            nofile: 100000

    DC1N2:
        image: cassandra:3.10
        command: bash -c 'if [ -z "$$(ls -A /var/lib/cassandra/)" ] ; then sleep 60; fi && /docker-entrypoint.sh cassandra -f'
        networks:
            - dc1ring
        volumes:
            - ./n2data:/var/lib/cassandra
        environment:
            - CASSANDRA_CLUSTER_NAME=Test Cluster
            - CASSANDRA_SEEDS=DC1N1
        depends_on:
              - DC1N1
        expose:
            - 7000
            - 7001
            - 7199
            - 9042
            - 9160
        ulimits:
            memlock: -1
            nproc: 32768
            nofile: 100000

    DC1N3:
        image: cassandra:3.10
        command: bash -c 'if [ -z "$$(ls -A /var/lib/cassandra/)" ] ; then sleep 120; fi && /docker-entrypoint.sh cassandra -f'
        networks:
            - dc1ring
        volumes:
            - ./n3data:/var/lib/cassandra
        environment:
            - CASSANDRA_CLUSTER_NAME=Test Cluster
            - CASSANDRA_SEEDS=DC1N1
        depends_on:
              - DC1N1
        expose:
            - 7000
            - 7001
            - 7199
            - 9042
            - 9160
        ulimits:
            memlock: -1
            nproc: 32768
            nofile: 100000

    # A web-based GUI for managing containers.
    portainer:
        image: portainer/portainer
        networks:
            - dc1ring
        volumes:
            - /var/run/docker.sock:/var/run/docker.sock
            - ./portainer-data:/data
        # Access to the web interface from the host via
        # http://localhost:10001
        ports:
            - "10001:9000"
networks:
    dc1ring: