Docker LAMP server - keep mysql between two operating systems - mysql

Question

I have one windows and one ubuntu 22.04 OS on my device. I have a special shared partition on my harddisk that I can enter from both of the OS'es.
On the shared partition I have a docker setup and I would like it to store the mysql data (volume) in a folder inside the host folder (./mysql_data)
The disk is mounted ntfs and thus, has as permission for all files and folders 1000:1000. Now, that is not docker (gid=999) so I have a hard time getting all permissions correct. Even when I set the -user 1000:1000 flag, issues keep piling up all the time:
corrupt files
not being able to login into phpmyadmin
permission issues
What would be a correct configuration for both the partition mount and the docker file?
partition mount (/etc/fstab):
UUID=xxx /mnt/share ntfs defaults,uid=1000,gid=999,fmask=0022,dmask=0000 0 0
docker-compose.yml:
version: "3.1"
services:
www:
build:
context: .
dockerfile: Dockerfile.lamp
user: 1000:1000
ports:
- "${WEBSERVER_PORT}:80"
volumes:
- ./www:/var/www/html/
links:
- db
networks:
- default
db:
image: mysql:8.0
user: 1000:1000
ports:
- "3306:3306"
command: --default-authentication-plugin=mysql_native_password
environment:
MYSQL_DATABASE: ${MYSQL_DATABASE}
MYSQL_USER: ${MYSQL_USER}
MYSQL_PASSWORD: ${MYSQL_PASSWORD}
MYSQL_ROOT_PASSWORD: ${MYSQL_PASSWORD}
volumes:
- ./sql:/docker-entrypoint-initdb.d
- ./conf:/etc/mysql/conf.d
- mysql_data:/var/lib/mysql
networks:
- default
phpmyadmin:
image: phpmyadmin/phpmyadmin
links:
- db:db
ports:
- ${PHPMYADMIN_PORT}:80
networks:
- default
environment:
MYSQL_USER: ${MYSQL_USER}
MYSQL_PASSWORD: ${MYSQL_PASSWORD}
MYSQL_ROOT_PASSWORD: ${MYSQL_PASSWORD}
UPLOAD_LIMIT: 64M
volumes:
mysql_data:
driver: local
driver_opts:
type: 'none'
o: 'bind'
device: './mysql_data'
networks:
default:
Any suggestions to how I could successfully achieve this? given that a mount has issues with permissions and will only set permissions on all files as given by the /etc/fstab file or default 1000:1000

Answer 1

Why default is 1000:1000?
The reason it set 1000:1000 as default is used to prevent docker created a file/folder own by root, once it own by root lot of situation will cause permission error if any process want to create or write file/folder, but if own by 1000:1000, you can change owner easily to which you want.
And also, set to 1000:1000 doesn't means you or any user have permissions to acceess with it, it still followed Linux permission rules, 1000:1000 is just Linux normal level user gid:uid count where it start with.
How mysql work around?
For example, Here is the mysql8.0 image (https://github.com/docker-library/mysql/blob/master/8.0/Dockerfile.oracle).
You can see it create a mysql:mysql user at beginning.
RUN set -eux; \
groupadd --system --gid 999 mysql; \
useradd --system --uid 999 --gid 999 --home-dir /var/lib/mysql --no-create-home mysql
And it changed these folders owner to mysql user on line 85, and it's the folder where mysql data stored by.
# ensure these directories exist and have useful permissions
# the rpm package has different opinions on the mode of `/var/run/mysqld`, so this needs to be after install
mkdir -p /var/lib/mysql /var/run/mysqld; \
chown mysql:mysql /var/lib/mysql /var/run/mysqld; \
# ensure that /var/run/mysqld (used for socket and lock files) is writable regardless of the UID our mysqld instance ends up having at runtime
chmod 1777 /var/lib/mysql /var/run/mysqld; \
What should you do?
Change your volume folder owner to which the container user, in mysql container you should change owner to mysql:mysql, or mysql won't able to write.
In other container do as same, change owner to which user your use to write/read, but docker compose can't volume as a specific user, so you might need try this: https://stackoverflow.com/a/56990338.
Notice that in your case user flag is not needed.