Docker Official Image Frequently Asked Questions

Frequently asked questions about the Docker Official Image

How to Reset Passwords

If you have an existing data directory and wish to reset the root and user passwords, and to create a database which the user can fully modify, perform the following steps.

First create a `passwordreset.sql` file:

CREATE USER IF NOT EXISTS root@localhost IDENTIFIED BY 'thisismyrootpassword';
SET PASSWORD FOR root@localhost = PASSWORD('thisismyrootpassword');
GRANT ALL ON *.* TO root@localhost WITH GRANT OPTION;
GRANT PROXY ON ''@'%' ON root@localhost WITH GRANT OPTION;
CREATE USER IF NOT EXISTS root@'%' IDENTIFIED BY 'thisismyrootpassword';
SET PASSWORD FOR root@'%' = PASSWORD('thisismyrootpassword');
GRANT ALL ON *.* TO root@'%' WITH GRANT OPTION;
GRANT PROXY ON ''@'%' ON root@'%' WITH GRANT OPTION;
CREATE USER IF NOT EXISTS myuser@'%' IDENTIFIED BY 'thisismyuserpassword';
SET PASSWORD FOR myuser@'%' = PASSWORD('thisismyuserpassword');
CREATE DATABASE IF NOT EXISTS databasename;
GRANT ALL ON databasename.* TO myuser@'%';

Adjust `myuser`, `databasename` and passwords as needed.

Then:

$ docker run --rm -v /my/own/datadir:/var/lib/mysql -v /my/own/passwordreset.sql:/passwordreset.sql:z %%IMAGE%%:latest --init-file=/passwordreset.sql

On restarting the MariaDB container in this `/my/own/datadir`, the `root` and `myuser` passwords will be reset.

Temp Server Start Timeout

Question, are you getting errors like the following where a temporary server start fails to succeed in 30 seconds?

Example of log:

2023-01-28 12:53:42+00:00 [Note] [Entrypoint]: Starting temporary server
2023-01-28 12:53:42+00:00 [Note] [Entrypoint]: Waiting for server startup
2023-01-28 12:53:42 0 [Note] mariadbd (server 10.10.2-MariaDB-1:10.10.2+maria~ubu2204) starting as process 72 ...
....
2023-01-28 12:53:42 0 [Note] InnoDB: Setting file './ibtmp1' size to 12.000MiB. Physically writing the file full; Please wait ...
2023-01-28 12:54:13 0 [Note] mariadbd: ready for connections.
Version: '10.10.2-MariaDB-1:10.10.2+maria~ubu2204'  socket: '/run/mysqld/mysqld.sock'  port: 0  mariadb.org binary distribution
2023-01-28 12:54:13+00:00 [ERROR] [Entrypoint]: Unable to start server.

The timeout on a temporary server start is a quite generous 30 seconds.

The lack of a message like the following indicates it failed to complete writing a temporary file of 12MiB in 30 seconds.

2023-01-28 12:53:46 0 [Note] InnoDB: File './ibtmp1' size is now 12.000MiB.

If the datadir where this is stored is remote storage maybe it's a bit slow. It's ideal to have an InnoDB temporary path local so this can be configured using the command or configuration setting:

innodb_temp_data_file_path=/dev/shm/ibtmp1:12M:autoextend

Note: depending on container runtime this space may be limited.

Creating a replication pair

`MARIADB_REPLICATION_USER` / `MARIADB_REPLICATION_PASSWORD` specify the authentication for the connection. The `MARIADB_MASTER_HOST` is the indicator that it is a replica and specifies the container aka hostname, of the master.

A `docker-compose.yml` example:

version: "3"
services:
  master:
    image: mariadb:latest
    command: --log-bin --log-basename=mariadb
    environment:
      - MARIADB_ROOT_PASSWORD=password
      - MARIADB_USER=testuser
      - MARIADB_PASSWORD=password
      - MARIADB_DATABASE=testdb
      - MARIADB_REPLICATION_USER=repl
      - MARIADB_REPLICATION_PASSWORD=replicationpass
    healthcheck:
      test: ["CMD", "healthcheck.sh", "--connect", "--innodb_initialized"]
      interval: 10s
      timeout: 5s
      retries: 3
  replica:
    image: mariadb:latest
    command: --server-id=2 --log-basename=mariadb
    environment:
      - MARIADB_ROOT_PASSWORD=password
      - MARIADB_MASTER_HOST=master
      - MARIADB_REPLICATION_USER=repl
      - MARIADB_REPLICATION_PASSWORD=replicationpass
      - MARIADB_HEALTHCHECK_GRANTS=REPLICA MONITOR
    healthcheck:
      test: ["CMD", "healthcheck.sh", "--connect", "--replication_io", "--replication_sql", "--replication_seconds_behind_master=1", "--replication"]
      interval: 10s
      timeout: 5s
      retries: 3
    depends_on:
      master:
        condition: service_healthy

InnoDB: Upgrade after a crash is not supported. The redo log was created with MariaDB X.Y.Z

This will show up in the error log as:

2022-05-23 12:29:20 0 [ERROR] InnoDB: Upgrade after a crash is not supported. The redo log was created with MariaDB 10.5.4.
2022-05-23 12:29:20 0 [ERROR] InnoDB: Plugin initialization aborted with error Generic error

This is attempting to start on a higher MariaDB version when the shutdown of the previous version crashed.

By crashed, it means the MariaDB was force killed or had a hard power failure. MariaDB, being a durable database, can recover from these, if started with the same version. The redo log however is a less stable format, so the recovery has to be on the same Major.Minor version, in this case 10.5. This error message is saying that you when from force killed MariaDB to a later version.

So whenever you encounter this message. Start with the again with the tag set to the version in the error message, like 10.5.4, or as the redo long format is consistent in the Major.Minor version 10.5 is sufficient. After this has been started correctly, cleanly shut the service down and it will be recovered.

The logs on shutdown should have a message like:

2023-11-06 10:49:23 0 [Note] InnoDB: Shutdown completed; log sequence number 84360; transaction id 49
2023-11-06 10:49:23 0 [Note] mariadbd: Shutdown complete

After you see this, you can update your MariaDB tag to a later version.

Every MariaDB start is a crash recovery

Do you get on every start:

db-1  | 2023-02-25 19:10:02 0 [Note] Starting MariaDB 10.11.2-MariaDB-1:10.11.2+maria~ubu2204-log source revision cafba8761af55ae16cc69c9b53a341340a845b36 as process 1                                                                                                         
db-1  | 2023-02-25 19:10:02 0 [Note] mariadbd: Aria engine: starting recovery                                                                                                                                                                                                   
db-1  | tables to flush: 3 2 1 0                                                                                                                                                                                                                                                
db-1  |  (0.0 seconds);                                                                                                                                                                                                                                                         
db-1  | 2023-02-25 19:10:02 0 [Note] mariadbd: Aria engine: recovery done  
...
db-1  | 2023-02-26 13:03:29 0 [Note] InnoDB: Initializing buffer pool, total size = 32.000GiB, chunk size = 512.000MiB
db-1  | 2023-02-26 13:03:29 0 [Note] InnoDB: Completed initialization of buffer pool
db-1  | 2023-02-26 13:03:29 0 [Note] InnoDB: File system buffers for log disabled (block size=512 bytes)
db-1  | 2023-02-26 13:03:29 0 [Note] InnoDB: Starting crash recovery from checkpoint LSN=193796878816

Container runtimes are assume to start and stop very quickly. Check the the shutdown logs. They may be a log like:

db-1  | 2023-02-26 13:03:17 0 [Note] InnoDB: Starting shutdown...                                                                                                                                                                                                               
db-1  | 2023-02-26 13:03:17 0 [Note] InnoDB: Dumping buffer pool(s) to /var/lib/mysql/ib_buffer_pool                                                                                                                                                                            
db-1  | 2023-02-26 13:03:17 0 [Note] InnoDB: Restricted to 519200 pages due to innodb_buf_pool_dump_pct=25                                                                                                                                                                      
db-1  | 2023-02-26 13:03:17 0 [Note] InnoDB: Buffer pool(s) dump completed at 230226 13:03:17                                                                                                                                                                                   
db-1 exited with code 0

Note that the logs didn't include the following messages:

db-1  | 2023-02-26 13:03:43 0 [Note] InnoDB: Shutdown completed; log sequence number 46590; transaction id 15
db-1  | 2023-02-26 13:03:43 0 [Note] mariadbd: Shutdown complete

As these messages aren't here, the container was killed off before it could just down cleanly. When this happens, the startup will be a crash recovery and you won't be able to upgrade your MariaDB instance (previous FAQ) to the next Major.Minor version.

Solution is to extend the timeout in the container runtime to allow MariaDB to complete its shutdown.