yidigun/mariadb-replication repository overview

⁠Mariadb Replication

Mariadb replication settings

⁠Mariadb License

See https://mariadb.com/kb/en/mariadb-license/⁠

⁠Dockerfile License

It's just free. (Public Domain)

See https://github.com/yidigun/mariadb-replication⁠

⁠Changelog

• 2024-09-14 - Fix scripts and configs for version 11
• 2024-08-26 - Upgrade to version 11
• 2022-02-18 - Change default locale to en_US.UTF-8, timezone to UTC. Locale and timezone is set automatically according to $LANG and $TZ envoringment variables.

⁠Supported tags

• 11.5.2-noble, 11.5.2, 11.5, 11, latest
• 10.11.9-jammy, 10.11.9, 10.11, 10 (not supported)
• 10.7-focal, 10.7 (not supported)

⁠Environment variables

• REPL_MODE: replication mode (required. none | master | slave)
• REPL_SERVER_ID: unique id for each server instance (required)
• REPL_USERNAME: replication username. password must be specified using PASSWORD_SECRET (default: repl)
• REPL_BACKUP: full path of backup copy to restore.
• REPL_MASTER_HOST: master servier's FQDN or address. (required for slave setup)
• REPL_MASTER_PORT: master servier's port. only for slave setup (default: 3306)
• PASSWORD_SECRET: password secret name (default: passwords)
• SSL_CERT_FILE: ssl certificate file
• SSL_CA_FILE: ssl ca certificate file
• SSL_KEY_FILE: ssl private-key file
• SSL_REQUIRE: require_secure_transport variable value
• MARIADB_PORT: service port (default: 3306)

⁠How to inject initial passwords

Make password config file using shell script syntax.

Format: USERNAME_PASSWORD="Password in plain text"

⁠passwords.sh

ROOT_PASSWORD="s3cret12#$"  # database admin
REPL_PASSWORD="cp1fly*"     # replication user

⁠docker-compose.yaml

...
services:
  mariadb:
    ...
    env:
      - REPL_USERNAME=repl
      - PASSWORD_SECRET=passwords
    ...
  secrets:
    passwords:
      - file: ${HOME}/passwords.sh

⁠Setting up Replication

See https://mariadb.com/kb/en/setting-up-a-replication-slave-with-mariabackup/⁠ for more details.

⁠1. Master setup

⁠1) passwords.sh

ROOT_PASSWORD="s3cret12#$"  # database admin
REPL_PASSWORD="cp1fly*"     # replication user

⁠2) docker-compose.yaml

version: "3.3"

services:
  mariadb-master:
    image: yidigun/mariadb-replication:10.7
    restart: unless-stopped
    hostname: ${HOSTNAME}
    ports:
      - "3306:3306/tcp"
    environment:
      - TZ=Asia/Seoul
      - LANG=ko_KR.UTF-8
      - REPL_MODE=master
      - REPL_SERVER_ID=1
      - REPL_USERNAME=repl
    volumes:
      - /data/mariadb/data:/var/lib/mysql
      - /data/mariadb/log:/var/log/mysql
      - /data/mariadb/run:/run/mysqld
      - /data/mariadb/snapshots:/snapshots
    secrets:
      - passwords

secrets:
  passwords:
    file: /path/to/passwords.sh

⁠3) Start master database

[MASTER]$ docker compose up -d

Start service and check master database work properly.

⁠2. Make backup and copy to slave server

First, make full backup of master server using mariabackup. Following command will create backup copy in /snapshots/snapshot-%Y%m%d. (eg: /snapshots/snapshot-20220210)

[MASTER]$ docker exec mariadb-master backup-master --no-lock

And move the backup files to slave server's /var/lib/mysql volume by any means.

[MASTER]$ (cd /data/mariadb/snapshots/snapshot-`date +%Y%m%d`; tar cf - *) | \
          ssh slave-server ' \
              sudo mkdir -p /data/mariadb/data; \
              (cd /data/mariadb/data; sudo tar xf -) && \
              sudo chown -R 999:999 /data/mariadb/data'

⁠3. Slave setup

⁠1) passwords.sh

REPL_PASSWORD="cp1fly*"     # replication user

⁠2) docker-compose.yaml

Note: REPL_SERVER_ID value must be unique in cluster.

version: "3.3"

services:
  mariadb-slave:
    image: yidigun/mariadb-replication:10.7
    restart: unless-stopped
    hostname: ${HOSTNAME}
    ports:
      - "3306:3306/tcp"
    environment:
      - TZ=Asia/Seoul
      - LANG=ko_KR.UTF-8
      - REPL_MODE=slave
      - REPL_SERVER_ID=2
      - REPL_USERNAME=repl
      - REPL_MASTER_HOST=mariadb-master.example.com
      - REPL_MASTER_PORT=3306
    volumes:
      - /data/mariadb/data:/var/lib/mysql
      - /data/mariadb/log:/var/log/mysql
      - /data/mariadb/run:/run/mysqld
    secrets:
      - passwords

secrets:
  passwords:
    file: /path/to/passwords.sh

⁠3) Start slave database

[SLAVE]$ docker compose up -d

⁠4) Start replication

Replication position will retrieved from /var/lib/mysql/xtrabackup_binlog_info. This file was generated when mariadb-backup (former mariabackup) make backup copy.

[SLAVE]$ docker exec mariadb-slave start-slave

⁠4. Check status

[MASTER]$ docker exec mariadb-master show-status
[SLAVE]$ docker exec mariadb-slave show-status