MySQL
Start a mysql
server instance
Starting a MySQL instance is simple:
docker run -itd --name mysql -p 3306:3306 -e MYSQL_ROOT_PASSWORD=123456 -v ~/Data\&Log/dockerdata/mysql/:/var/lib/mysql -d mysql
Environment Variables
When you start the mysql
image, you can adjust the configuration of the MySQL instance by passing one or more environment variables on the docker run
command line. Do note that none of the variables below will have any effect if you start the container with a data directory that already contains a database: any pre-existing database will always be left untouched on container startup.
See also https://dev.mysql.com/doc/refman/5.7/en/environment-variables.html for documentation of environment variables which MySQL itself respects (especially variables like MYSQL_HOST
, which is known to cause issues when used with this image).
MYSQL_ROOT_PASSWORD
This variable is mandatory and specifies the password that will be set for the MySQL root
superuser account. In the above example, it was set to my-secret-pw
.
MYSQL_DATABASE
This variable is optional and allows you to specify the name of a database to be created on image startup. If a user/password was supplied (see below) then that user will be granted superuser access (corresponding to GRANT ALL
) to this database.
MYSQL_USER
, MYSQL_PASSWORD
These variables are optional, used in conjunction to create a new user and to set that user's password. This user will be granted superuser permissions (see above) for the database specified by the MYSQL_DATABASE
variable. Both variables are required for a user to be created.
Do note that there is no need to use this mechanism to create the root superuser, that user gets created by default with the password specified by the MYSQL_ROOT_PASSWORD
variable.
MYSQL_ALLOW_EMPTY_PASSWORD
This is an optional variable. Set to a non-empty value, like yes
, to allow the container to be started with a blank password for the root user. NOTE: Setting this variable to yes
is not recommended unless you really know what you are doing, since this will leave your MySQL instance completely unprotected, allowing anyone to gain complete superuser access.
MYSQL_RANDOM_ROOT_PASSWORD
This is an optional variable. Set to a non-empty value, like yes
, to generate a random initial password for the root user (using pwgen
). The generated root password will be printed to stdout (GENERATED ROOT PASSWORD: .....
).
MYSQL_ONETIME_PASSWORD
Sets root (not the user specified in MYSQL_USER
!) user as expired once init is complete, forcing a password change on first login. Any non-empty value will activate this setting. NOTE: This feature is supported on MySQL 5.6+ only. Using this option on MySQL 5.5 will throw an appropriate error during initialization.
MYSQL_INITDB_SKIP_TZINFO
By default, the entrypoint script automatically loads the timezone data needed for the CONVERT_TZ()
function. If it is not needed, any non-empty value disables timezone loading.
Docker Secrets
As an alternative to passing sensitive information via environment variables, _FILE
may be appended to 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 some-mysql -e MYSQL_ROOT_PASSWORD_FILE=/run/secrets/mysql-root -d mysql:tag
Currently, this is only supported for MYSQL_ROOT_PASSWORD
, MYSQL_ROOT_HOST
, MYSQL_DATABASE
, MYSQL_USER
, and MYSQL_PASSWORD
.
Where to Store Data
Important note: There are several ways to store data used by applications that run in Docker containers. We encourage users of the mysql
images to familiarize themselves with the options available, including:
- Let Docker manage the storage of your database data by writing the database files to disk on the host system using its own internal volume management. This is the default and is easy and fairly transparent to the user. The downside is that the files may be hard to locate for tools and applications that run directly on the host system, i.e. outside containers.
- Create a data directory on the host system (outside the container) and mount this to a directory visible from inside the container. This places the database files in a known location on the host system, and makes it easy for tools and applications on the host system to access the files. The downside is that the user needs to make sure that the directory exists, and that e.g. directory permissions and other security mechanisms on the host system are set up correctly.
The Docker documentation is a good starting point for understanding the different storage options and variations, and there are multiple blogs and forum postings that discuss and give advice in this area. We will simply show the basic procedure here for the latter option above:
-
Create a data directory on a suitable volume on your host system, e.g.
/my/own/datadir
. -
Start your
mysql
container like this:$ docker run --name some-mysql -v /my/own/datadir:/var/lib/mysql -e MYSQL_ROOT_PASSWORD=my-secret-pw -d mysql:tag
The -v /my/own/datadir:/var/lib/mysql
part of the command mounts the /my/own/datadir
directory from the underlying host system as /var/lib/mysql
inside the container, where MySQL by default will write its data files.
MongoDB
docker run --name mongo -p 27017:27017 -v ~/Data\&Log/dockerdata/mongo:/data/db -e MONGO_INITDB_ROOT_USERNAME=admin -e MONGO_INITDB_ROOT_PASSWORD=admin -d mongo