How to fix bitnami mariadb 'mkdir: cannot create directory '/bitnami/mariadb': Permission denied'

Problem:

You are trying to run a docker bitnami/mariadb container but when you try to start it up, you see an error message like

mariadb_1   | mkdir: cannot create directory '/bitnami/mariadb': Permission denied

Solution

bitnami containers mostly are non-root-containers, hence you need to adjust the permissions for the data directory mapped onto the host.

First, find out what directory your /bitnami is mapped to on the host. For example, for

services:
    mariadb:
        image: 'bitnami/mariadb:latest'
        environment:
            - ALLOW_EMPTY_PASSWORD=yes
        volumes:
            - '/var/lib/my_docker/mariadb_data:/bitnami'

it is mapped to /var/lib/my_docker/mariadb_data.

Now chown this directory to 1001:1001 since the image is using UID 1001 as the user running the command:

sudo chown -R 1001:1001 [directory]

for example

sudo chown -R 1001:1001 /var/lib/my_docker/mariadb_data