Docker AutoMySQLBackup

A lightweight image for creating and managing scheduled MySQL backups. Runs a slightly modified AutoMySQLBackup utility.

Supported tags and respective Dockerfile links

• 2.7.0 2.7.0-mysql8.0 latest (Dockerfile), main image with mysql8 client
• 2.7.0-mysql5.7 (Dockerfile), version with mysql5.7 client

Version

This image uses AutoMySQLBackup 2.5 from Debian Linux source repository as a base, branched at 2.6+debian.4-1 tag. Original source can be cloned from git://anonscm.debian.org/users/zigo/automysqlbackup.git or taken at the appropriate Debian package page.

Custom modifications:

• passed logging to stdout/stderr
• removed error logs mailing code
• made default configuration more suitable for docker container

Image usage

Let's create a bridge network and start a MySQL container as an example.

docker network create dbtest
docker run --name some-mysql --network dbtest \
    -e MYSQL_ROOT_PASSWORD=my-secret-pw -d mysql:latest

For the basic one-shot backup, you can run a container like this:

docker run --network dbtest \
    -v '/var/lib/automysqlbackup:/backup' \
    -e DBHOST=some-mysql \
    -e DBNAMES=all \
    -e USERNAME=root \
    -e PASSWORD=my-secret-pw \
    -e DBNAMES=all \
    automysqlbackup:2.7.0

Container will create dumps of all datebases from MySQL inside /var/lib/automysqlbackup directory and exit.

To run container in a scheduled mode, populate CRON_SCHEDULE environment variable with a cron expression.

docker run --network dbtest \
    -v '/var/lib/automysqlbackup:/backup' \
    -e DBHOST=some-mysql \
    -e DBNAMES=all \
    -e USERNAME=root \
    -e PASSWORD=my-secret-pw \
    -e DBNAMES=all \
    -e CRON_SCHEDULE="0 0 * * *" \
    automysqlbackup:2.7.0

Instead of passing environment variables though docker, you can also mount a file with their declarations as volume. See defaults file in this image's git repository for the example.

docker run --network dbtest \
    -v '/var/lib/automysqlbackup:/backup' \
    -v '/etc/default/automysqlbackup:/etc/default/automysqlbackup:ro' \
    automysqlbackup:2.7.0

Usage with docker-compose

For the example of using this image with docker-compose, see docker-compose.yml file in the image's repository.

Quick tips:

• You can call automysqlbackup binary directly for the manual backup: docker-compose exec mysqlbackup automysqlbackup
• Use only YAML dictionary for passing CRON_SCHEDULE environment variable CRON_SCHEDULE: "0 0 * * *" as YAML sequence - CRON_SCHEDULE="0 * * * *" will preserve quotes breaking go-cron (Issue #1).

Environment variables

• CRON_SCHEDULE
  If set to cron expression, container will start a cron daemon for scheduled backups.

• USERNAME
  Username to access the MySQL server.

• PASSWORD
  Password to access the MySQL server.

• DBHOST
  Host name (or IP address) of MySQL server.

• DBPORT
  Port of MySQL server.

• DBNAMES
  List of space separated database names for Daily/Weekly Backup. Set to all for all databases.
  Default value: all

• BACKUPDIR
  Backup directory location. Folders inside this one will be created (daily, weekly, etc.), and the subfolders will be database names.
  Default value: /backup

• MDBNAMES
  List of space separated database names for Monthly Backups.
  Will mirror DBNAMES if DBNAMES set to all.

• DBEXCLUDE
  List of DBNAMES to exclude if DBNAMES are set to all (must be in " quotes).

• IGNORE_TABLES
  List of space separated table names in a format of db_name.tbl_name to exclude from backup (must be in " quotes).

• CREATE_DATABASE
  Include CREATE DATABASE in backup?
  Default value: yes

• SEPDIR
  Separate backup directory and file for each DB? (yes or no).
  Default value: yes

• DOWEEKLY
  Which day do you want weekly backups? (1 to 7 where 1 is Monday).
  Default value: 6

• COMP
  Choose Compression type. (gzip or bzip2)
  Default value: gzip

• COMMCOMP
  Compress communications between backup server and MySQL server?
  Default value: no

• LATEST
  Additionally keep a copy of the most recent backup in a seperate directory.
  Default value: no

• MAX_ALLOWED_PACKET
  The maximum size of the buffer for client/server communication. e.g. 16MB (maximum is 1GB)

• SOCKET
  For connections to localhost. Sometimes the Unix socket file must be specified.

• PREBACKUP
  Command to run before backups

• POSTBACKUP
  Command run after backups

• ROUTINES
  Backup of stored procedures and routines
  Default value: yes

• EXTRA_OPTS
  Pass any arbitrary flags to mysqldump, e.g. --single-transaction.

• USER_ID Run the backup process from the specified user id. Allows matching backup files permissions with the host's user.
  Default value: 1 (root).

• GROUP_ID Run the backup process from the specified group id. Allows matching backup files permissions with the host's group.
  If empty, matches USER_ID.

Docker Secrets

As an alternative to passing sensitive information via environment variables, _FILE may be appended to some of the previously listed environment variables, causing the initialization script to load the values for those variables from files present in the container. In particular, this can be used to load passwords from Docker secrets stored in /run/secrets/<secret_name> files. For example:

docker run --name automysqlbackup -e USERNAME=root -e PASSWORD_FILE=/run/secrets/mysql_root_password automysqlbackup

Currently, this is only supported for USERNAME and PASSWORD.

FAQ

• Will you add support for AutoMySQLBackup 3?
  No. AutoMySQLBackup 3 was a complete rewrite of the script with much higher complexity but was abandoned in 2011 before it released. There are multiple repositories which try to support it by fixing bugs and ensuring compatibility with newer MySQL versions but I don't have time to track changes in those to properly support docker image.

• Can you add CONFIG_* option
  Those options appeared in AutoMySQLBackup 3. See the above question.

License

Similar to the original automysqlbackup script, all sources for this image are licensed under GPL-2.0.