Permissions on Docker Created Files

[joshso]

Hi! Newbie here. (Really neat app btw Jesse!)

I run a NAS 24x7 (Unraid) and would prefer to host ytdl-sub there via Docker so that I can automate it over time. My problem is when I create files via the container, the default owner and permissions are such that I receive errors when I try to move/delete/rename using smb, connecting as my preferred username of josh.

I understand this is down to PUID/PGID/UMASK. The challenge is they look correct. Here's my work, do you spy what I'm missing?

Docker creating files as: root
I prefer Docker to be creating files as: josh

Example files and folders created from either Samba or the container:
ls -al

-rw-r--r-- 1 root root 0 Jul 4 13:44 aDockerCreatedFile
drwxr-xr-x 1 root root 0 Jul 4 13:49 aDockerCreatedFolder/
-rw-rw-rw- 1 josh users 0 Jul 4 13:35 aSambaCreatedFile
drwxrwxrwx 1 josh users 0 Jul 4 13:49 aSambaCreatedFolder/

This is after setting PUID=1000, PGID=100 and UMASK=000. (I cannot tell UMASK doing anything and am guessing it is setting the user side, not root?)

At least when I query umask from within the container I get the default 0022:
umask

0022

I can see the proper variable values are being passed as desired:

docker exec ytdl-sub /usr/bin/env

PATH=/lsiopy/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME=2b735f346fab
DOCKER_MODS=linuxserver/mods:universal-cron
TZ=America/New_York
HOST_OS=Unraid
HOST_HOSTNAME=Tower
HOST_CONTAINERNAME=ytdl-sub
PUID=1000
PGID=100
UMASK=000
PS1=$(whoami)@$(hostname):$(pwd)$
HOME=/config
TERM=xterm
S6_CMD_WAIT_FOR_SERVICES_MAXTIME=0
S6_VERBOSITY=1
S6_STAGE2_HOOK=/docker-mods
VIRTUAL_ENV=/lsiopy
EDITOR=nano

Here's the output of id:
id josh

uid=1000(josh) gid=100(users) groups=100(users)`

While I have other docker applications running, I have never attempted to create files on the NAS from a container itself. From research I am only 80% confident that I would expect the docker created files to be owned by username=josh, group=users and with a mask of 666 (since I am setting a umask of 000). Am I wrong on expected behavior?

[jmbannon]

The docker container uses the username abc, which should be 1000:100. When you log into the container, you need to do docker exec -u abc ytdl-sub /bin/bash, otherwise you log in as root and it will create files using the root user

[nick-roux]

I'm running the ubuntu docker image on a Synology NAS.

Before I ran build docker_ubuntu to create the image, I edited Dockerfile.ubuntu by adding the following

Below ARG DEBIAN_FRONTEND=noninteractive

Change this to match the existing user details on your NAS

ARG USERNAME=ytdl
ARG USER_UID=1099
ARG USER_GID=100

Below the existing RUN command in the dockerfile

RUN useradd --uid $USER_UID --gid $USER_GID -M $USERNAME

Below HOME="/config"

USER ytdl

Below VOLUME /config

VOLUME /video
VOLUME /music
VOLUME /music_videos

Now your container will run under container user ytdl and access the host filesystems with host user ytdl. Anything new created in /video /music etc will be owned by user ytdl

You can also do this if you use the alpine image,, but note that the adduser command has different syntax on alpine and will need to be changed accordingly

[jmbannon]

The abc user will use the PUID and PGID values defined in the docker env, why not use that vs creating a new ytdl user?