777 make the mounted custom mysql config file my.cnf didn’t take effect, 444 fix it when use docker image mariadb Today I add a custom config file my.cnf and mount it to docker iamge’s /etc/mysql ### Mariadb Container ####################################### mariadb: image: mariadb:10.4 volumes: - ./mariadb:/var/lib/mysql - ./etc/mysql/my.cnf:/etc/mysql/my.cnf environment: - MYSQL_ROOT_PASSWORD=password ports: - 3306:3306 container_name: mariadb restart: always networks: - backend But the config didn’t take effect, after some investigation, I find the permissoin of my file my.cnf is 777 After I change the permission of my.cnf to 0444(chmod 0444 my.cnf), then the config take effect.