Docker: Permission denied to local MySQL volume - linux

Question

I'm new with Docker and I don't know Linux well. I'm trying to build my own environment for local development with Docker. I’m using docker-compose utility. I want to store MySQL data in the local volume. When I run docker-compose build and docker-compose up -d commands for the first time, there are no errors. Data from MySQL container goes into the local folder. Everything works well except one: when I want to change my docker-compose.yml file and rebuild containers I get an error
vo#vo-ThinkPad-Edge-E330:~/www/test$ docker-compose build
mysql uses an image, skipping
nginx uses an image, skipping
Building app
Traceback (most recent call last):
File "bin/docker-compose", line 3, in <module>
File "compose/cli/main.py", line 67, in main
File "compose/cli/main.py", line 126, in perform_command
File "compose/cli/main.py", line 302, in build
File "compose/project.py", line 468, in build
File "compose/project.py", line 450, in build_service
File "compose/service.py", line 1125, in build
File "docker/api/build.py", line 160, in build
File "docker/utils/build.py", line 30, in tar
File "docker/utils/build.py", line 49, in exclude_paths
File "docker/utils/build.py", line 214, in rec_walk
File "docker/utils/build.py", line 214, in rec_walk
File "docker/utils/build.py", line 214, in rec_walk
[Previous line repeated 1 more time]
File "docker/utils/build.py", line 184, in rec_walk
PermissionError: [Errno 13] Permission denied: '/home/vo/www/test/docker/mysql/dbdata/performance_schema'
[301838] Failed to execute script docker-compose
I found out that the owner of the folder is systemd-coredump from root group. So I have 2 ways:
sudo docker-compose build
Delete /home/vo/www/test/docker/mysql/dbdata folder with sudo permissions and run docker-compose build again.
So, my question: Is this how it should be or is it possible to solve the permissions problem?
My project structure:
/
├── docker
│   ├── mysql
│   │   ├── conf
│   │   │   └── my.cnf
│   │   └── dbdata
│   ├── nginx
│   │   └── conf
│   │   └── nginx.conf
│   └── php
│   ├── conf
│   │   └── local.ini
│   ├── config
│   │   └── local.ini
│   └── Dockerfile
├── docker-compose.yml
└── src
My docker-compose.yml:
version: "3.7"
services:
#PHP Service
app:
build:
args:
user: laravel
uid: 1000
context: ./
dockerfile: ./docker/php/Dockerfile
image: laravel-image
container_name: laravel
restart: unless-stopped
tty: true
environment:
SERVICE_NAME: app
SERVICE_TAGS: dev
working_dir: /var/www/
volumes:
- ./src:/var/www
- ./docker/php/config/local.ini:/usr/local/etc/php/conf.d/local.ini
networks:
- laravel
#MySQL Service
mysql:
image: mysql:5.7
container_name: mysql
restart: unless-stopped
tty: true
ports:
- "3306:3306"
environment:
MYSQL_DATABASE: laravel
MYSQL_ROOT_PASSWORD: secret
MYSQL_PASSWORD: secret
MYSQL_USER: laravel
SERVICE_TAGS: dev
SERVICE_NAME: mysql
volumes:
- ./docker/mysql/dbdata:/var/lib/mysql
- ./docker/mysql/conf/my.cnf:/etc/mysql/my.cnf
networks:
- laravel
#Nginx Service
nginx:
image: nginx:1.17-alpine
container_name: nginx
restart: unless-stopped
tty: true
ports:
- "80:80"
- "443:443"
environment:
SERVICE_NAME: nginx
SERVICE_TAGS: dev
volumes:
- ./src:/var/www
- ./docker/nginx/conf:/etc/nginx/conf.d
networks:
- laravel
#Networks
networks:
laravel:
driver: bridge

Answer 1

Ok, I found a trick. In my docker-compose.yml in service volume section I have to use named volumes instead of path. For example, 'mysqldbvolume' instead of './docker/mysql/dbdata'. Then I have to define a named volume in the top-level volumes key:
services:
#MySQL Service
mysql:
image: mysql:5.7
...
volumes:
- mysqldbvolume:/var/lib/mysql
- ./docker/mysql/conf/my.cnf:/etc/mysql/my.cnf
...
...
# Volumes
volumes:
mysqldbvolume:
driver: local
So, where is my volume now? If I want to see list of my volumes, I have to run docker volume ls:
DRIVER VOLUME NAME
local test_mysqldbvolume
local test_postgresdbvolume
Inspect volume - docker volume inspect test_mysqldbvolume:
[
{
"CreatedAt": "2020-12-17T21:54:53+02:00",
"Driver": "local",
"Labels": {
"com.docker.compose.project": "test",
"com.docker.compose.version": "1.27.4",
"com.docker.compose.volume": "mysqldbvolume"
},
"Mountpoint": "/var/lib/docker/volumes/test_mysqldbvolume/_data",
"Name": "test_mysqldbvolume",
"Options": null,
"Scope": "local"
}
]
So, path is "Mountpoint": "/var/lib/docker/volumes/test_mysqldbvolume/_data"
Run with regular user ls -la /var/lib/docker/volumes/test_mysqldbvolume/_data says access is denied. But if I run sudo ls -la /var/lib/docker/volumes/test_mysqldbvolume/_data I see my volume data:
drwxrwxrwt 6 systemd-coredump systemd-coredump 4096 дек 17 21:54 .
drwxr-xr-x 3 root root 4096 дек 17 21:42 ..
-rw-r----- 1 systemd-coredump systemd-coredump 56 дек 17 21:42 auto.cnf
-rw------- 1 systemd-coredump systemd-coredump 1676 дек 17 21:42 ca-key.pem
-rw-r--r-- 1 systemd-coredump systemd-coredump 1112 дек 17 21:42 ca.pem
-rw-r--r-- 1 systemd-coredump systemd-coredump 1112 дек 17 21:42 client-cert.pem
-rw------- 1 systemd-coredump systemd-coredump 1680 дек 17 21:42 client-key.pem
-rw-r----- 1 systemd-coredump systemd-coredump 2 дек 17 21:54 ed50eca9e01e.pid
-rw-r----- 1 systemd-coredump systemd-coredump 6093953 дек 17 21:54 general.log
-rw-r----- 1 systemd-coredump systemd-coredump 445 дек 17 21:49 ib_buffer_pool
-rw-r----- 1 systemd-coredump systemd-coredump 79691776 дек 17 21:54 ibdata1
-rw-r----- 1 systemd-coredump systemd-coredump 50331648 дек 17 21:54 ib_logfile0
-rw-r----- 1 systemd-coredump systemd-coredump 50331648 дек 17 21:42 ib_logfile1
-rw-r----- 1 systemd-coredump systemd-coredump 12582912 дек 17 21:54 ibtmp1
drwxr-x--- 2 systemd-coredump systemd-coredump 4096 дек 17 21:47 laravel
drwxr-x--- 2 systemd-coredump systemd-coredump 4096 дек 17 21:42 mysql
drwxr-x--- 2 systemd-coredump systemd-coredump 4096 дек 17 21:42 performance_schema
-rw------- 1 systemd-coredump systemd-coredump 1680 дек 17 21:42 private_key.pem
-rw-r--r-- 1 systemd-coredump systemd-coredump 452 дек 17 21:42 public_key.pem
-rw-r--r-- 1 systemd-coredump systemd-coredump 1112 дек 17 21:42 server-cert.pem
-rw------- 1 systemd-coredump systemd-coredump 1680 дек 17 21:42 server-key.pem
drwxr-x--- 2 systemd-coredump systemd-coredump 12288 дек 17 21:42 sys
Most importantly, the permission error is gone.

Answer 2

I had this issue too but for a different reason than the majority of answers here.
I have a dual boot setup with a 2nd disk accessible to both Linux and Windows.
I had my docker images and code on the 2nd disk, an NTFS-3G drive. I tried all workarounds with chmod and chown but it just would not work.
When the penny dropped NTFS-3G was causing the issue, I moved Docker back to the default configuration with everything on the system disk including the code of my project.
Images & containers were once again in the default location /var/lib/docker and my code I moved to ~/code/project.
Once I did this, all permission issues went away.