Remove VOLUME directive

[ericjacolin]

I needed to bind the container Apache virtual host configuration and the Apache and certbot log file locations from a persistent disk instead of volumes, which is what one typically wants to do on a production environment

services:
    apache-proxy:
        build:
            context: "docker-apache-letsencrypt"
        restart: always
        ports:
            - "80:80"
            - "443:443"
        volumes:
            - "${PDISK_MNT}/etc/letsencrypt:/etc/letsencrypt"
            - "${PDISK_MNT}/etc/apache-proxy/sites-enabled:/etc/apache2/sites-enabled"
            - "${PDISK_MNT}/log/letsencrypt:/var/log/letsencrypt"
            - "${PDISK_MNT}/log/apache-proxy:/var/log/apache2"

Since it is not possible to override a parent VOLUME directive, I could not extend the image but had to clone the Dockerfile and remove the VOLUME directive, which is not ideal. Removing the VOLUME directive would give more flexibility to users.

[BirgerK]

Of course it is possible to mount paths from native host, if those paths were declared as VOLUME.

From documentation (https://docs.docker.com/v17.09/engine/reference/builder/#understand-how-cmd-and-entrypoint-interact) :

The VOLUME instruction creates a mount point with the specified name and marks it as holding externally mounted volumes from native host or other containers.

I'm also using this image with a lot of mounted paths.

Which error messages do you see if you try it?

[ericjacolin]

Thanks I gave it a try and indeed it seems that the VOLUME directive is harmless here. This article helped me better understand why. Closing the issue.

[ericjacolin]

Closed