Change file permissions in mounted folder inside docker container on Windows Host

Question

Disclaimer/Edit 2

Some years later, for everyone reading this question - If you are on Windows and want to use docker with linux containers, I highly recommend not using docker for windows at all and instead starting the entire docker environment inside a VM altogether. This Ext3 NTFS issue will break your neck on so many different levels that installing docker-machine might not even be worth the effort.

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Edit:

I am using docker-machine which starts a boot2docker instance inside a Virtualbox VM with a shared folder on /c/Users from which you can mount volumes into your containers. The permissions of said volumes are the ones the question is about. The VMs are stored under /c/Users/tom/.docker/

I chose to use the docker-machine Virtualbox workflow over Hyper-V because I need VBox in my daily workflow and running Hyper-V and Virtualbox together on one system is not possible due to incompabilities between different Hypervisors.

Original question

I am currently trying to set up PHPMyAdmin in a container on windows but I can't change the permissions of the config.inc.php file.

I found: Cannot call chown inside Docker container (Docker for Windows) and thought this might be somewhat related but it appears to apply only to MongoDB.

This is my docker-compose.yml

    version: "3"

    services:
      pma:
        image: (secrect company registry)/phpmyadmin
        ports: 
          - 9090:80
        volumes:
          - /c/Users/tom/projects/myproject/data/var/www/public/config.inc.php:/var/www/public/config.inc.php

now, when I docker exec -it [container] bash and change in the mounted directory, I try to run chmod on the config.inc.php but for some reason, it fails silently.

root@22a4bag43245: ls -la config.inc.php
-rw------- 1 root root 0 Aug 11 15:11 config.inc.php
root@22a4bag43245: chmod 655 config.inc.php
root@22a4bag43245: ls -la config.inc.php
-rw------- 1 root root 0 Aug 11 15:11 config.inc.php

Considering the linked answer, I thought I could just move the volume out of my Userhome but then vbox doesn't mount the folder at all.

How do I change the file permissions of /var/www/public/config.inc.php persistently?

Answer 1

Try one of the following:

1. If you can rebuild the image image: image: (secrect company registry)/docker-stretchimal-apache2-php7-pma then inside the docker file, add the following

   USER root RUN chmod 655 config.inc.php

Then you can rebuild the image and push it to the registry, and what you were doing should work. This should be your preferred solution, as you don't want to be manually changing the permissions everytime you start a new container

2. Try to exec using the user root explicitly

   docker exec -it -u root [container] bash