docker-composeでMySQLレプリケーション構築

ディレクトリ構成

.
├── docker/
│   ├── primary/
│   │   ├── Dockerfile
│   │   ├── init.sh*
│   │   ├── mysql.cnf
│   │   └── mysqld.cnf
│   └── replica/
│       ├── Dockerfile
│       ├── dockerize-linux-amd64-v0.6.1.tar.gz
│       ├── init.sh*
│       ├── mysql.cnf
│       └── mysqld.cnf
└── docker-compose.yml

Primary

mysqld.cnf

[mysqld]
:
log-bin=ON
server-id=1
gtid-mode=ON
enforce-gtid-consistency=ON
log-slave-updates=ON

init.sh

#!/bin/bash
set -xeo pipefail

mysql -uroot -v <<SQL
CREATE USER 'repl'@'172.16.0.0/255.240.0.0' IDENTIFIED BY 'replpass';
GRANT REPLICATION SLAVE ON *.* TO 'repl'@'172.16.0.0/255.240.0.0';
SQL

Dockerfile

FROM mysql
COPY mysql.cnf /etc/mysql/conf.d/mysql.cnf
COPY mysqld.cnf /etc/mysql/conf.d/mysqld.cnf
COPY init.sh /docker-entrypoint-initdb.d/init.sh

Secondary

mysqld.cnf

[mysqld]
:
log-bin=ON
server-id=2
gtid-mode=ON
enforce-gtid-consistency=ON
log-slave-updates=ON
read-only=ON

init.sh

#!/bin/bash
set -xeo pipefail

dockerize -timeout 60s -wait tcp://primary:3306
sleep 3

mysql -uroot -v <<SQL
CHANGE MASTER TO MASTER_HOST='primary', MASTER_USER='repl', MASTER_PASSWORD='replpass', MASTER_AUTO_POSITION=1;
START SLAVE;
SQL

Dockerfile

FROM mysql
COPY mysql.cnf /etc/mysql/conf.d/mysql.cnf
COPY mysqld.cnf /etc/mysql/conf.d/mysqld.cnf
COPY init.sh /docker-entrypoint-initdb.d/init.sh

# dockerize
COPY dockerize-linux-amd64-v0.6.1.tar.gz /tmp/
RUN tar -xzf /tmp/dockerize-linux-amd64-v0.6.1.tar.gz -C /usr/local/bin

Docker Compose

docker-compose.yml

version: '3'
services:
  primary:
    build:
      context: ./docker/primary
    environment:
      MYSQL_ALLOW_EMPTY_PASSWORD: 1
    ports:
      - 33061:3306
    volumes:
      - type: volume
        source: primary
        target: /var/lib/mysql
  replica:
    build:
      context: ./docker/replica
    depends_on:
      - primary
    environment:
      MYSQL_ALLOW_EMPTY_PASSWORD: 1
    ports:
      - 33062:3306
    volumes:
      - type: volume
        source: replica
        target: /var/lib/mysql
volumes:
  primary:
  replica: