Running Percona Server for MySQL in a Docker Container¶
Percona Server for MySQL has an official Docker image hosted on Docker Hub. If you want the latest version, use the latest tag. You can reference a specific version using the Docker tag filter for the 8.0 versions.
Make sure that you are using the latest version of Docker. The apt and yum versions may be outdated and cause errors.
Starting a detached container¶
You can start a background container with the --detached or -d option, which runs the container in the background. In detached mode, the container exits when the root process used to run the container exits.
The following example starts a container named ps with the latest version of
Percona Server for MySQL 8.0. This action also creates the root user and uses root as the password. Please note that root is not a secure password.
$ docker run -d \
--name ps \
-e MYSQL_ROOT_PASSWORD=root \
percona/percona-server:8.0
Expected output
Unable to find image 'percona/percona-server:8.0' locally
8.0: Pulling from percona/percona-server
By default, Docker pulls the image from Docker Hub if it is not available locally.
To view the container’s logs, use the following command:
docker logs ps --follow
Expected output
Initializing database
2022-09-07T15:20:03.158128Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.29-21) initializing of server in progress as process 15
2022-09-07T15:20:03.167764Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2022-09-07T15:20:03.530600Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
2022-09-07T15:20:04.367600Z 0 [Warning] [MY-013829] [Server] Missing data directory for ICU regular expressions: /usr/lib64/mysql/private/.
...
2022-09-07T15:20:13.706090Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/lib/mysql/mysqlx.sock
2022-09-07T15:20:13.706136Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.29-21' socket: '/var/lib/mysql/mysql.sock' port: 3306 Percona Server (GPL), Release 21, Revision c59f87d2854.
You can access the server when you see the ready for connections information in the log.
Passing Options¶
You can pass options with the docker run command. For example, the following command uses UTF-8 as the default setting for character set and collation for all databases:
[root@docker-host] $ docker run -d \
--name ps \
-e MYSQL_ROOT_PASSWORD=root \
percona/percona-server:8.0 \
--character-set-server=utf8 \
--collation-server=utf8_general_ci
Accessing the Percona Server Container¶
The docker exec command lets you have a shell inside the container. This command uses it which forwards your input stream as an interactive TTY.
An example of accessing the detached container:
[root@docker-host] $ docker exec -it ps /bin/bash
If you need to troubleshoot, the error log is found in /var/log/ or /var/log/mysql/. The file name may be error.log or mysqld.log.
Troubleshooting¶
You can view the error log with the following command:
[mysql@ps] $ more /var/log/mysql/error.log
Expected output
...
2017-08-29T04:20:22.190474Z 0 [Warning] 'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
2017-08-29T04:20:22.190520Z 0 [Warning] 'NO_AUTO_CREATE_USER' sql mode was not set.
...
Accessing the database¶
You can access the database either with Docker exec or using the mysql command in the container’s shell.
An example of using Docker exec to access the database:
$ docker exec -ti ps mysql -uroot -proot
Expected output
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 9
...
Exiting Percona Server also exits the container.
You can also run the MySQL command-line client within the container’s shell to access the database:
[mysql@ps] $ mysql -uroot -proot
Expected output
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.29-21 Percona Server (GPL), Release 21, Revision c59f87d2854
Copyright (c) 2009-2022 Percona LLC and/or its affiliates
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
Accessing the server from an application in another container¶
The image exposes the standard MySQL port 3306,
so container linking makes the Percona Server instance available
from other containers.
To link a container running your application
(in this case, from an image named app/image)
with the Percona Server container,
run it with the following command:
[root@docker-host] $ docker run -d \
--name app \
--link ps \
app/image:latest
This application container will be able to access the Percona Server container via port 3306.
Storing data¶
There are two ways to store data used by applications that run in Docker containers:
-
Let Docker manage the storage of your data by writing the database files to disk on the host system using its internal volume management.
-
Create a data directory on the host system on high-performance storage and mount it to a directory visible from the container. This method 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 user should ensure that the directory exists, that the user accounts have required permissions, and that any other security mechanisms on the host system are set up correctly.
For example, if you create a data directory on a suitable volume
on your host system named /local/datadir,
you run the container with the following command:
[root@docker-host] $ docker run -d \
--name ps \
-e MYSQL_ROOT_PASSWORD=root \
-v /local/datadir:/var/lib/mysql \
percona/percona-server:8.0
The -v /local/datadir:/var/lib/mysql option
mounts the /local/datadir directory on the host
to /var/lib/mysql in the container,
which is the default data directory used by Percona Server for MySQL.
Do not add MYSQL_ROOT_PASSWORD to the docker run command if the data directory contains subdirectories, files, or data.
Note
If you have SELinux enabled, assign the relevant policy type to the new data directory so that the container will be allowed to access it:
[root@docker-host] $ chcon -Rt svirt_sandbox_file_t /local/datadir
Port forwarding¶
Docker allows mapping ports on the container to ports on the host system
using the -p option.
If you run the container with this option,
you can connect to the database by connecting your client
to a port on the host machine.
This ability simplifies consolidating instances to a single host.
To map the standard MySQL port 3306 to port 6603 on the host:
[root@docker-host] $ docker run -d \
--name ps \
-e MYSQL_ROOT_PASSWORD=root \
-p 6603:3306 \
percona/percona-server:8.0
Exiting the container¶
If you are in the interactive shell, use CTRL-D or exit to exit the session.
If you have a non-shell process running, interrupt the process with CTRL-C before using either CTRL-D or exit.
Stopping the container¶
The docker stop container command sends a TERM signal, then waits 10 seconds and sends a KILL signal. The following example stops the ps container:
$ docker stop ps
The default length of time before stopping a container is 10 seconds. A very large instance cannot dump the data from memory to disk within that time. With this type of instance, add the --time or the -t option to docker stop:
$ docker stop ps -t 600
Removing the container¶
To remove a stopped container, use the docker rm command.
$ docker rm ps
For more information¶
Review the Docker Docs
