Basic Docker Compose and Build a Redis Cluster with Docker Compose

Docker Compose

As demonstrated in the Redis Cluster example above, we need to create numerous containers and manage aspects such as networking and data volumes for these containers. Handling these tasks one by one with individual Docker commands can be cumbersome. Therefore, Docker Compose can address this issue.

Docker Compose can be used to define and run multiple containers, configuring the services of an application through a YAML file. Subsequently, a single command can be used to create and start all services based on the configuration.

Create a yaml file
Command: $ nano docker-compose.yaml

# docker-compose.yml
services:
    test:
        image: redis

Usage

# Under your docker compose file's path
$ docker compose up # Execute (similar with docker run -it)
$ docker compose up -d  # Execute the container in background (similar with docker run -d)
# If your docker compose yaml file name is not called "docker-compose.yaml"
$ docker-compose -f /path/to/your/project/your-custom-name.yml up -d


# Check container
$ docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED         STATUS         PORTS      NAMES
4035917143c5   redis     "docker-entrypoint.s…"   4 minutes ago   Up 3 minutes   6379/tcp   docker-compose-testing-test-1

Docker compose yaml details:

Reference: https://docs.docker.com/compose/compose-file/

Top level:

1. services: Configuration of the container, you can think that it is similar with the docker run command.
2. networks: Custom Network Manage.create the custom network, and the services side can reference this network configuration, it can be used with several services at the same time.
3. volumes: Managing volumes. Can be used with several services at the same time.
4. version: Docker compose version.

#top level:
version: "2.21"
services:
    nginx-demo:     # service name (create a container), it's not a container name
        container_name: nginx-1
        image: nginx    # image name
        restart: always     # optional: restart strategy
        networks:   # reference with networks top level
            - my-frontend-network  # you can call/reference the custom network
        volumes:    # reference with volumes top level
            - nginx_volume:/usr/share/nginx/html  # call the specific volume
        environment:
            APP_ENV: dev
        dns: 8.8.8.8
        depends_on:
            - db    # Build this container (nginx) after the container in db section created
        ports:
            - 8000:80

    # other service (create other container)
    db:
        image: mysql
        container_name: mysql-1
        volumes:
            - db_volume:/var/lib/mysql
        networks:
            - my-frontend-network
        environment:
            MYSQL_ROOT_PASSWORD: 123456
        ports: 33060:3306


networks:   # top level
    my-frontend-network:     # name of network for services side reference it
        name: app-network   # name of customer network
        driver: bridge
        ipam:
            driver: default
            config:
                - subnet: 172.28.0.0/16
                  ip_range: 172.28.5.0/24
                  gateway: 172.28.5.254
                  aux_addresses:
                    host1: 172.28.1.5
                    host2: 172.28.1.6
                    host3: 172.28.1.7
            options:
                foo: bar
                bax: "0"

volumes:  # top level
    db_volume:
        name: "mysql-volume"
    nginx_volume:
        name: "nginx-volume"

Docker compose command:
There are many command similar with docker.

Options:
      --ansi string                Control when to print ANSI control characters
                                   ("never"|"always"|"auto") (default "auto")
      --compatibility              Run compose in backward compatibility mode
      --dry-run                    Execute command in dry run mode
      --env-file stringArray       Specify an alternate environment file.
  -f, --file stringArray           Compose configuration files
      --parallel int               Control max parallelism, -1 for unlimited (default -1)
      --profile stringArray        Specify a profile to enable
      --progress string            Set type of progress output (auto, tty, plain, quiet) (default "auto")
      --project-directory string   Specify an alternate working directory
                                   (default: the path of the, first specified, Compose file)
  -p, --project-name string        Project name

Commands:
  build       Build or rebuild services
  config      Parse, resolve and render compose file in canonical format
  cp          Copy files/folders between a service container and the local filesystem
  create      Creates containers for a service.
  down        Stop and remove containers, networks
  events      Receive real time events from containers.
  exec        Execute a command in a running container.
  images      List images used by the created containers
  kill        Force stop service containers.
  logs        View output from containers
  ls          List running compose projects
  pause       Pause services
  port        Print the public port for a port binding.
  ps          List containers
  pull        Pull service images
  push        Push service images
  restart     Restart service containers
  rm          Removes stopped service containers
  run         Run a one-off command on a service.
  start       Start services
  stop        Stop services
  top         Display the running processes
  unpause     Unpause services
  up          Create and start containers
  version     Show the Docker Compose version information
  wait        Block until the first service container stops

1. docker compose config: Parse, resolve and render compose file in canonical format

# it can check your docker-compose.yml file is correct or not
$ docker compose config
ERROR: In file './docker-compose.yml', volume 'db_volume' must be a mapping not an array.

# Successful Case:
$ docker compose config # if no error, return back the details information
name: docker-compose-testing
services:
  db:
    ...
  nginx-demo:
    ...
    volumes:    # in config will show some details information
    - type: volume
      source: nginx_volume
      target: /usr/share/nginx/html
      volume: {}
networks:
    ...

volumes:
  ...

2. docker compose create <service_name>: docker-compose.yaml file can create many images at the same time, but you can using this command to create a specific image and run container.

$ docker compose create db # create mysql
[+] Creating 2/0
 ✔ Volume "mysql-volume"  Created                                                                        0.0s
 ✔ Container mysql-1      Created

3. docker compose up: create and run all service (container)

$ docker compose up -d  # -d option: run in background
[+] Running 3/3
 ✔ Network app-network  Created                                                                                                            0.1s
 ✔ Container mysql-1    Started                                                                                                            0.0s
 ✔ Container nginx-1    Started

4. docker compose ps: check the running compose container

$ docker compose ps
NAME      IMAGE     COMMAND                                          SERVICE      CREATED         STATUS         PORTS
mysql-1   mysql     "docker-entrypoint.sh mysqld"                    db           8 minutes ago   Up 8 minutes   33060/tcp, 0.0.0.0:33060->3306/tcp, :::33060->3306/tcp
nginx-1   nginx     "/docker-entrypoint.sh nginx -g 'daemon off;'"   nginx-demo   8 minutes ago   Up 8 minutes   0.0.0.0:8000->80/tcp, :::8000->80/tcp

5. docker compose down: Deleted anythings created by this docker compose

$ docker compose down
[+] Running 3/3
 ✔ Container mysql-1                       Removed                                                       0.0s
 ✔ Network docker-compose-testing_default  Removed                                                       0.6s
 ✔ Network app-network                     Removed

6. docker compose images

$ docker compose images
CONTAINER           REPOSITORY          TAG                 IMAGE ID            SIZE
mysql-1             mysql               latest              73246731c4b0        619MB
# Successful

$ docker compose ps -a
NAME      IMAGE     COMMAND                         SERVICE   CREATED         STATUS    PORTS
mysql-1   mysql     "docker-entrypoint.sh mysqld"   db        2 minutes ago   Created

Build a Redis Cluster with Docker Compose

Create volume (mount) file first:

# run this for loop to create each redis container configuration file
for port in $(seq 1 6); do
  mkdir -p /redis/node-${port}/conf
  touch /redis/node-${port}/conf/redis.conf
  cat << EOF >/redis/node-${port}/conf/redis.conf
port 6379
bind 0.0.0.0
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
cluster-announce-ip 172.38.0.1${port}
cluster-announce-port 6379
cluster-announce-bus-port 16379
appendonly yes
EOF
done

Write the docker-compose.yaml file:

version: "3"
services:
    redis-1:
        image: redis
        command: ["redis-server","/etc/redis/redis.conf"]
        volumes:
            - /redis/node-1/data:/data
            - /redis/node-1/conf/redis.conf:/etc/redis/redis.conf
        ports:
            - 6371:6379
            - 16371:16379
        networks:
            redis_network:
                ipv4_address: 172.38.0.11
    redis-2:
        image: redis
        command: ["redis-server", "/etc/redis/redis.conf"]
        volumes:
            - /redis/node-2/data:/data
            - /redis/node-2/conf/redis.conf:/etc/redis/redis.conf
        ports:
            - "6372:6379"
            - 16372:16379
        networks:
            redis_network:
                ipv4_address: 172.38.0.12
    redis-3:
        image: redis
        command: ["redis-server", "/etc/redis/redis.conf"]
        volumes:
            - /redis/node-3/data:/data
            - /redis/node-3/conf/redis.conf:/etc/redis/redis.conf
        ports:
            - "6373:6379"
            - 16373:16379
        networks:
            redis_network:
                ipv4_address: 172.38.0.13
    redis-4:
        image: redis
        command: ["redis-server", "/etc/redis/redis.conf"]
        volumes:
            - /redis/node-4/data:/data
            - /redis/node-4/conf/redis.conf:/etc/redis/redis.conf
        ports:
            - "6374:6379"
            - 16374:16379
        networks:
            redis_network:
                ipv4_address: 172.38.0.14
    redis-5:
        image: redis
        command: ["redis-server", "/etc/redis/redis.conf"]
        volumes:
            - /redis/node-5/data:/data
            - /redis/node-5/conf/redis.conf:/etc/redis/redis.conf
        ports:
            - "6375:6379"
            - 16375:16379
        networks:
            redis_network:
                ipv4_address: 172.38.0.15
    redis-6:
        image: redis
        command: ["redis-server", "/etc/redis/redis.conf"]
        volumes:
            - /redis/node-6/data:/data
            - /redis/node-6/conf/redis.conf:/etc/redis/redis.conf
        ports:
            - "6376:6379"
            - "16376:16379"
        networks:
            redis_network:
                ipv4_address: 172.38.0.16
networks:
    redis_network:
        driver: bridge
        ipam:
            config:
                - subnet: 172.38.0.0/16
                  gateway: 172.38.0.1

Command:

# check docker-compose.yaml is correct or not
$ docker compose config

# Run docker compose
root@jielim36:/home/jielim36/redis-cluster-docker-compose# docker compose up -d
[+] Running 7/7
 ✔ Network redis-cluster-docker-compose_redis_network  Created                                                                             0.1s
 ✔ Container redis-cluster-docker-compose-redis-4-1    Started                                                                             0.1s
 ✔ Container redis-cluster-docker-compose-redis-3-1    Started                                                                             0.1s
 ✔ Container redis-cluster-docker-compose-redis-5-1    Started                                                                             0.1s
 ✔ Container redis-cluster-docker-compose-redis-1-1    Started                                                                             0.1s
 ✔ Container redis-cluster-docker-compose-redis-6-1    Started                                                                             0.1s
 ✔ Container redis-cluster-docker-compose-redis-2-1    Started                                                                             0.1s

# check running container
$ docker compose ps
NAME                                     IMAGE     COMMAND                                                     SERVICE   CREATED          STATUS          PORTS
redis-cluster-docker-compose-redis-1-1   redis     "docker-entrypoint.sh redis-server /etc/redis/redis.conf"   redis-1   23 seconds ago   Up 20 seconds   0.0.0.0:6371->6379/tcp, :::6371->6379/tcp, 0.0.0.0:16371->16379/tcp, :::16371->16379/tcp
redis-cluster-docker-compose-redis-2-1   redis     "docker-entrypoint.sh redis-server /etc/redis/redis.conf"   redis-2   23 seconds ago   Up 20 seconds   0.0.0.0:6372->6379/tcp, :::6372->6379/tcp, 0.0.0.0:16372->16379/tcp, :::16372->16379/tcp
redis-cluster-docker-compose-redis-3-1   redis     "docker-entrypoint.sh redis-server /etc/redis/redis.conf"   redis-3   23 seconds ago   Up 20 seconds   0.0.0.0:6373->6379/tcp, :::6373->6379/tcp, 0.0.0.0:16373->16379/tcp, :::16373->16379/tcp
redis-cluster-docker-compose-redis-4-1   redis     "docker-entrypoint.sh redis-server /etc/redis/redis.conf"   redis-4   23 seconds ago   Up 20 seconds   0.0.0.0:6374->6379/tcp, :::6374->6379/tcp, 0.0.0.0:16374->16379/tcp, :::16374->16379/tcp
redis-cluster-docker-compose-redis-5-1   redis     "docker-entrypoint.sh redis-server /etc/redis/redis.conf"   redis-5   23 seconds ago   Up 20 seconds   0.0.0.0:6375->6379/tcp, :::6375->6379/tcp, 0.0.0.0:16375->16379/tcp, :::16375->16379/tcp
redis-cluster-docker-compose-redis-6-1   redis     "docker-entrypoint.sh redis-server /etc/redis/redis.conf"   redis-6   23 seconds ago   Up 20 seconds   0.0.0.0:6376->6379/tcp, :::6376->6379/tcp, 0.0.0.0:16376->16379/tcp, :::16376->16379/tcp

# If created successful, enter to the redis-1 to create cluster
$ redis-cli --cluster create 172.38.0.11:6379 172.38.0.12:6379 172.38.0.13:6379 172.38.0.14:6379 172.38.0.15:6379 172.38.0.16:6379 --cluster-replicas 1

# Check again, enter to the redis-cli with cluster
root@b59ad0535541:/data$ redis-cli -c
# check the relationship of all redis nodes
127.0.0.1:6379> cluster nodes
94cce23d515a45ca974016bebf8354c939cd686b 172.38.0.11:6379@16379 myself,master - 0 1705657020000 1 connected 0-5460
2ddaeb2cbce78eee11d02de916ef87ed9cd02a1a 172.38.0.12:6379@16379 master - 0 1705657020000 2 connected 5461-10922
c77d4c93aa9ee2abb593abacfd9cfd7a5caae0df 172.38.0.13:6379@16379 master - 0 1705657021585 3 connected 10923-16383
af8f4638ff90e4aa04797a0cb6fa6a517ed041d4 172.38.0.15:6379@16379 slave 94cce23d515a45ca974016bebf8354c939cd686b 0 1705657021585 1 connected
18c33a87f82726cbc77cf67f7a72fdd6ecc15dda 172.38.0.16:6379@16379 slave 2ddaeb2cbce78eee11d02de916ef87ed9cd02a1a 0 1705657020000 2 connected
2fb725e35588b2edc34d8d3bc09d85593f2fd963 172.38.0.14:6379@16379 slave c77d4c93aa9ee2abb593abacfd9cfd7a5caae0df 0 1705657021000 3 connected

Command: $ redis-cli --cluster create 172.38.0.11:6379 172.38.0.12:6379 172.38.0.13:6379 172.38.0.14:6379 172.38.0.15:6379 172.38.0.16:6379 --cluster-replicas 1

• redis-cli: Redis command-line client tool.
• --cluster create: Command to create a Redis cluster.
• 172.38.0.11:6379 172.38.0.12:6379 172.38.0.13:6379 172.38.0.14:6379 172.38.0.15:6379 172.38.0.16:6379: Lists the various nodes in the cluster, including their IP addresses and port numbers. Here, 6 nodes are listed.
• --cluster-replicas 1: Sets the number of replicas for each master node to 1, meaning each master node will have one corresponding replica node.

You can provide more or fewer nodes as needed, and Redis will automatically configure the cluster accordingly. In this example, Redis inferred that you intended to create a cluster with 3 master nodes, each having a corresponding replica node.

Redis Cluster Relationship Diagram:

Usage:

# Enter into redis client with cluster mode
$ redis-cli -c
127.0.0.1:6379>

# Check cluster
127.0.0.1:6379> cluster nodes
11ef9dda18ee2fed754e5ce8baf0b04c2686ce56 172.38.0.12:6379@16379 master - 0 1705549415000 2 connected 5461-10922
b795fbd6344355a3a8d8bc9eae43b09553430874 172.38.0.16:6379@16379 slave 11ef9dda18ee2fed754e5ce8baf0b04c2686ce56 0 1705549416000 2 connected
b0954d066f6119abb5cc94307d7f66f6dabeaec4 172.38.0.15:6379@16379 slave 6d3685e325d476fadb9e0bd49a39b8406d9431a9 0 1705549416526 1 connected
6d3685e325d476fadb9e0bd49a39b8406d9431a9 172.38.0.11:6379@16379 myself,master - 0 1705549415000 1 connected 0-5460
900fb4a71efc86030b42230b10de2d25942c9e9a 172.38.0.14:6379@16379 slave e66e9af15132cd2b89f55b5fb890d2f18627aeed 0 1705549415000 3 connected
e66e9af15132cd2b89f55b5fb890d2f18627aeed 172.38.0.13:6379@16379 master - 0 1705549416426 3 connected 10923-16383

# usage
127.0.0.1:6379> set a b
-> Redirected to slot [15495] located at 172.38.0.13:6379   # it is save in node 3 (master)
OK
172.38.0.13:6379> get a
"b"

172.38.0.13:6379> set key01 value01
OK
172.38.0.13:6379> get key01
"value01"

# We known the data is save in redis-3, we try to stop this container
# In linux
root@jielim36:/home/jielim36# docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED          STATUS          PORTS                                                                                      NAMES
ccc478e3cb5f   redis     "docker-entrypoint.s…"   35 minutes ago   Up 35 minutes   0.0.0.0:6376->6379/tcp, :::6376->6379/tcp, 0.0.0.0:16376->16379/tcp, :::16376->16379/tcp   redis-6
c78636d05676   redis     "docker-entrypoint.s…"   36 minutes ago   Up 36 minutes   0.0.0.0:6375->6379/tcp, :::6375->6379/tcp, 0.0.0.0:16375->16379/tcp, :::16375->16379/tcp   redis-5
b701b548cdf8   redis     "docker-entrypoint.s…"   37 minutes ago   Up 37 minutes   0.0.0.0:6374->6379/tcp, :::6374->6379/tcp, 0.0.0.0:16374->16379/tcp, :::16374->16379/tcp   redis-4
7176ac3adb31   redis     "docker-entrypoint.s…"   37 minutes ago   Up 37 minutes   0.0.0.0:6373->6379/tcp, :::6373->6379/tcp, 0.0.0.0:16373->16379/tcp, :::16373->16379/tcp   redis-3
ac8020c72f3f   redis     "docker-entrypoint.s…"   37 minutes ago   Up 37 minutes   0.0.0.0:6372->6379/tcp, :::6372->6379/tcp, 0.0.0.0:16372->16379/tcp, :::16372->16379/tcp   redis-2
3918d85a6719   redis     "docker-entrypoint.s…"   40 minutes ago   Up 40 minutes   0.0.0.0:6371->6379/tcp, :::6371->6379/tcp, 0.0.0.0:16371->16379/tcp, :::16371->16379/tcp   redis-1

# stop the redis-3
root@jielim36:/home/jielim36: docker stop redis-3
redis-3

# And we go back to the redis, and trying to get the key "a" again
127.0.0.1:6379> get a
-> Redirected to slot [15495] located at 172.38.0.14:6379   # As you can see, you can get the data from the redis-4 now (slave node of the redis-3)
"b"  # retrieve data successful