docker-documentation/images/docker-openssh-server.md

linuxserver/openssh-server

Openssh-server is a sandboxed environment that allows ssh access without giving keys to the entire server. Giving ssh access via private key often means giving full access to the server. This container creates a limited and sandboxed environment that others can ssh into. The users only have access to the folders mapped and the processes running inside this container.

Supported Architectures

Our images support multiple architectures such as x86-64, arm64 and armhf. We utilise the docker manifest for multi-platform awareness. More information is available from docker here and our announcement here.

Simply pulling linuxserver/openssh-server should retrieve the correct image for your arch, but you can also pull specific arch images via tags.

The architectures supported by this image are:

Architecture	Tag
x86-64	amd64-latest
arm64	arm64v8-latest
armhf	arm32v7-latest

Usage

Here are some example snippets to help you get started creating a container from this image.

docker

docker create \
  --name=openssh-server \
  --hostname=openssh-server `#optional` \
  -e PUID=1000 \
  -e PGID=1000 \
  -e TZ=Europe/London \
  -e PUBLIC_KEY=yourpublickey `#optional` \
  -e PUBLIC_KEY_FILE=/path/to/file `#optional` \
  -e SUDO_ACCESS=false `#optional` \
  -e PASSWORD_ACCESS=false `#optional` \
  -e USER_PASSWORD=password `#optional` \
  -e USER_PASSWORD_FILE=/path/to/file `#optional` \
  -e USER_NAME=linuxserver.io `#optional` \
  -p 2222:2222 \
  -v /path/to/appdata/config:/config \
  --restart unless-stopped \
  linuxserver/openssh-server

docker-compose

Compatible with docker-compose v2 schemas.

---
version: "2"
services:
  openssh-server:
    image: linuxserver/openssh-server
    container_name: openssh-server
    hostname: openssh-server #optional
    environment:
      - PUID=1000
      - PGID=1000
      - TZ=Europe/London
      - PUBLIC_KEY=yourpublickey #optional
      - PUBLIC_KEY_FILE=/path/to/file #optional
      - SUDO_ACCESS=false #optional
      - PASSWORD_ACCESS=false #optional
      - USER_PASSWORD=password #optional
      - USER_PASSWORD_FILE=/path/to/file #optional
      - USER_NAME=linuxserver.io #optional
    volumes:
      - /path/to/appdata/config:/config
    ports:
      - 2222:2222
    restart: unless-stopped

Parameters

Docker images are configured using parameters passed at runtime (such as those above). These parameters are separated by a colon and indicate <external>:<internal> respectively. For example, -p 8080:80 would expose port 80 from inside the container to be accessible from the host's IP on port 8080 outside the container.

Ports (-p)

Parameter	Function
2222	ssh port

Environment Variables (-e)

Env	Function
PUID=1000	for UserID - see below for explanation
PGID=1000	for GroupID - see below for explanation
TZ=Europe/London	Specify a timezone to use EG Europe/London
PUBLIC_KEY=yourpublickey	Optional ssh public key, which will automatically be added to authorized_keys.
PUBLIC_KEY_FILE=/path/to/file	Optionally specify a file containing the public key (works with docker secrets).
SUDO_ACCESS=false	Set to true to allow linuxserver.io, the ssh user, sudo access. Without USER_PASSWORD set, this will allow passwordless sudo access.
PASSWORD_ACCESS=false	Set to true to allow user/password ssh access. You will want to set USER_PASSWORD or USER_PASSWORD_FILE as well.
USER_PASSWORD=password	Optionally set a sudo password for linuxserver.io, the ssh user. If this or USER_PASSWORD_FILE are not set but SUDO_ACCESS is set to true, the user will have passwordless sudo access.
USER_PASSWORD_FILE=/path/to/file	Optionally specify a file that contains the password. This setting supersedes the USER_PASSWORD option (works with docker secrets).
USER_NAME=linuxserver.io	Optionally specify a user name (Default:linuxserver.io)

Volume Mappings (-v)

Volume	Function
/config	Contains all relevant configuration files.

User / Group Identifiers

When using volumes (-v flags), permissions issues can arise between the host OS and the container, we avoid this issue by allowing you to specify the user PUID and group PGID.

Ensure any volume directories on the host are owned by the same user you specify and any permissions issues will vanish like magic.

In this instance PUID=1000 and PGID=1000, to find yours use id user as below:

  $ id username
    uid=1000(dockeruser) gid=1000(dockergroup) groups=1000(dockergroup)

Application Setup

If PUBLIC_KEY or PUBLIC_KEY_FILE variables are set, they will automatically be added to authorized_keys. If not, the keys can manually be added to /config/.ssh/authorized_keys and the container should be restarted. Removing PUBLIC_KEY or PUBLIC_KEY_FILE variables from docker run environment variables will not remove the keys from authorized_keys. PUBLIC_KEY_FILE can be used with docker secrets.

We provide the ability to set and allow password based access via the PASSWORD_ACCESS and USER_PASSWORD variables, though we as an organization discourage using password auth for public facing ssh endpoints.

Connect to server via ssh -i /path/to/private/key -p PORT USER_NAME@SERVERIP

Setting SUDO_ACCESS to true by itself will allow passwordless sudo. USER_PASSWORD and USER_PASSWORD_FILE allow setting an optional sudo password.

The users only have access to the folders mapped and the processes running inside this container.
Add any volume mappings you like for the users to have access to.
To install packages or services for users to access, use the LinuxServer container customization methods described in this blog article.

Sample use case is when a server admin would like to have automated incoming backups from a remote server to the local server, but they might not want all the other admins of the remote server to have full access to the local server.
This container can be set up with a mounted folder for incoming backups, and rsync installed via LinuxServer container customization described above, so that the incoming backups can proceed, but remote server and its admins' access would be limited to the backup folder.

It is also possible to run multiple copies of this container with different ports mapped, different folders mounted and access to different private keys for compartmentalized access.

TIPS
You can volume map your own text file to /etc/motd to override the message displayed upon connection.
You can optionally set the docker argument hostname

Support Info

• Shell access whilst the container is running:
  • docker exec -it openssh-server /bin/bash
• To monitor the logs of the container in realtime:
  • docker logs -f openssh-server
• Container version number
  • docker inspect -f '{{ index .Config.Labels "build_version" }}' openssh-server
• Image version number
  • docker inspect -f '{{ index .Config.Labels "build_version" }}' linuxserver/openssh-server

Versions

• 19.12.19: - Rebasing to alpine 3.11.
• 17.10.19: - Initial Release.