Regular backup an DB found in the mysql linked as "mysql" to the voloume /var/dbdumps.

Setup

You have to:

• run the container dsteinkopf/backup-all-mysql
• create a link called mysql to you db to be backed up.
• Create a volume called /var/dbdumps.

Environment

• Interval may be set via environment BACKUP_INTERVAL (in seconds).
• Use BACKUP_FIRSTDELAY to delay the very first backup to be done by n seconds. The idea behind this is to prevent existing backups to be overwritten in case of problems. So you can manually kill everything an try again within this delay.
• MYSQLDUMP_ADD_OPTS (default = ""): More options to be added to mysqldump.
• MYSQL_CONNECTION_PARAMS (default = ""): More mysql option to add to any mysql command (incl. mysqldump)
• MYSQL_HOST (default = "mysql"): Hostname (or IP) of mysql database.
• MYSQL_USER (default = "root"): Username to connect to mysql database.
• MYSQL_PASSWORD ( use MYSQL_ENV_MYSQL_ROOT_PASSWORD if available ): The password to connect to mysql .
• USE_PIPE_TO_BZ (default = 1): If 1 then mysqldump directly pipes to lbzip2 instead of using a temp file (saves disk space but takes longer)

MYSQLDUMP_ADD_OPTS, MYSQL_CONNECTION_PARAMS, MYSQL_HOST, MYSQL_USER , MYSQL_PASSWORD, can be used with suffix _FILE, if stored in a file . This is usefull for docker secrets (only available for swarm mode), or to hide sensitive data in general ( like MYSQL_PASSWORD ) .

Example : MYSQL_PASSWORD_FILE=/run/secrets/mysql-root Will read the file /run/secrets/mysql-root, and copy the content in the env var MYSQL_PASSWORD

Monitoring

For an easy monitoring of successful backup an error file /var/dbdumps/errorslastrun.log is created (in volume /var/dbddumps. This file contains errors if there were any - it is empty if everything was ok.

So to monitor correct backup you should

• check that errorslastrun.log is empty.
• chat that errorslastrun.log is touched (modification date changed) regularly (see env BACKUP_INTERVAL).

Usage example

In docker-compose.yml:

mysql-backup:

  image: dsteinkopf/backup-all-mysql:latest
  environment:
    - BACKUP_INTERVAL=20000
    - BACKUP_FIRSTDELAY=3600
  links:
    - mysql
  restart: always
  volumes:
    - /opt/dockervolumes/wordpress/mysql-backup:/var/dbdumps
    - /etc/localtime:/etc/localtime
    - /etc/timezone:/etc/timezone

In docker-compose.yml, for swarm, with secrets ( secrets is already setup ) :

version: '3.2'

services:
  backup:
    image: dsteinkopf/backup-all-mysql:latest
    environment:
      - BACKUP_INTERVAL=21600 #6h
      - BACKUP_FIRSTDELAY=3600
      - MYSQL_HOST=mariadb
      - MYSQL_ENV_MYSQL_ROOT_PASSWORD_FILE=/run/secrets/mysql-pwd
    restart: always
    volumes:
      - /opt/dockervolumes/wordpress/mysql-backup:/var/dbdumps
      - /etc/localtime:/etc/localtime
      - /etc/timezone:/etc/timezone
    secrets:
      - mysql-pwd

  mariadb:
    image: mariadb:latest
    secrets:
      - mysql-pwd
    restart: always
    environment:
      MYSQL_ROOT_PASSWORD_FILE: /run/secrets/mysql-pwd

secrets:
  mysql-pwd:
    external: true

-> for example found in my Zabbix Setup (German language)