17 KiB
title |
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openssh-server |
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
We utilise the docker manifest for multi-platform awareness. More information is available from docker here and our announcement here.
Simply pulling lscr.io/linuxserver/openssh-server:latest
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 | Available | Tag |
---|---|---|
x86-64 | ✅ | amd64-<version tag> |
arm64 | ✅ | arm64v8-<version tag> |
armhf | ❌ |
Application Setup
If PUBLIC_KEY
or PUBLIC_KEY_FILE
, or PUBLIC_KEY_DIR
variables are set, the specified keys 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
and PUBLIC_KEY_DIR
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
Key Generation
This container has a helper script to generate an ssh private/public key. In order to generate a key please run:
docker run --rm -it --entrypoint /keygen.sh linuxserver/openssh-server
Then simply follow the prompts. The keys generated by this script are only displayed on your console output, so make sure to save them somewhere after generation.
Usage
To help you get started creating a container from this image you can either use docker-compose or the docker cli.
docker-compose (recommended, click here for more info)
---
version: "2.1"
services:
openssh-server:
image: lscr.io/linuxserver/openssh-server:latest
container_name: openssh-server
hostname: openssh-server #optional
environment:
- PUID=1000
- PGID=1000
- TZ=Etc/UTC
- PUBLIC_KEY=yourpublickey #optional
- PUBLIC_KEY_FILE=/path/to/file #optional
- PUBLIC_KEY_DIR=/path/to/directory/containing/_only_/pubkeys #optional
- PUBLIC_KEY_URL=https://github.com/username.keys #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
docker cli (click here for more info)
docker run -d \
--name=openssh-server \
--hostname=openssh-server `#optional` \
-e PUID=1000 \
-e PGID=1000 \
-e TZ=Etc/UTC \
-e PUBLIC_KEY=yourpublickey `#optional` \
-e PUBLIC_KEY_FILE=/path/to/file `#optional` \
-e PUBLIC_KEY_DIR=/path/to/directory/containing/_only_/pubkeys `#optional` \
-e PUBLIC_KEY_URL=https://github.com/username.keys `#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 \
lscr.io/linuxserver/openssh-server:latest
Parameters
Containers 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=Etc/UTC |
specify a timezone to use, see this list. |
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). |
PUBLIC_KEY_DIR=/path/to/directory/containing/_only_/pubkeys |
Optionally specify a directory containing the public keys (works with docker secrets). |
PUBLIC_KEY_URL=https://github.com/username.keys |
Optionally specify a URL containing the public key. |
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. |
Miscellaneous Options
Parameter | Function |
---|---|
--hostname= |
Optionally the hostname can be defined. |
Environment variables from files (Docker secrets)
You can set any environment variable from a file by using a special prepend FILE__
.
As an example:
-e FILE__MYVAR=/run/secrets/mysecretvariable
Will set the environment variable MYVAR
based on the contents of the /run/secrets/mysecretvariable
file.
Umask for running applications
For all of our images we provide the ability to override the default umask settings for services started within the containers using the optional -e UMASK=022
setting.
Keep in mind umask is not chmod it subtracts from permissions based on it's value it does not add. Please read up here before asking for support.
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 your_user
as below:
id your_user
Example output:
uid=1000(your_user) gid=1000(your_user) groups=1000(your_user)
Docker Mods
We publish various Docker Mods to enable additional functionality within the containers. The list of Mods available for this image (if any) as well as universal mods that can be applied to any one of our images can be accessed via the dynamic badges above.
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" }}' lscr.io/linuxserver/openssh-server:latest
Updating Info
Most of our images are static, versioned, and require an image update and container recreation to update the app inside. With some exceptions (ie. nextcloud, plex), we do not recommend or support updating apps inside the container. Please consult the Application Setup section above to see if it is recommended for the image.
Below are the instructions for updating containers:
Via Docker Compose
-
Update images:
-
All images:
docker-compose pull
-
Single image:
docker-compose pull openssh-server
-
-
Update containers:
-
All containers:
docker-compose up -d
-
Single container:
docker-compose up -d openssh-server
-
-
You can also remove the old dangling images:
docker image prune
Via Docker Run
-
Update the image:
docker pull lscr.io/linuxserver/openssh-server:latest
-
Stop the running container:
docker stop openssh-server
-
Delete the container:
docker rm openssh-server
-
Recreate a new container with the same docker run parameters as instructed above (if mapped correctly to a host folder, your
/config
folder and settings will be preserved) -
You can also remove the old dangling images:
docker image prune
Via Watchtower auto-updater (only use if you don't remember the original parameters)
-
Pull the latest image at its tag and replace it with the same env variables in one run:
docker run --rm \ -v /var/run/docker.sock:/var/run/docker.sock \ containrrr/watchtower \ --run-once openssh-server
-
You can also remove the old dangling images:
docker image prune
!!! warning
We do not endorse the use of Watchtower as a solution to automated updates of existing Docker containers. In fact we generally discourage automated updates. However, this is a useful tool for one-time manual updates of containers where you have forgotten the original parameters. In the long term, we highly recommend using [Docker Compose](https://docs.linuxserver.io/general/docker-compose).
Image Update Notifications - Diun (Docker Image Update Notifier)
!!! tip
We recommend [Diun](https://crazymax.dev/diun/) for update notifications. Other tools that automatically update containers unattended are not recommended or supported.
Building locally
If you want to make local modifications to these images for development purposes or just to customize the logic:
git clone https://github.com/linuxserver/docker-openssh-server.git
cd docker-openssh-server
docker build \
--no-cache \
--pull \
-t lscr.io/linuxserver/openssh-server:latest .
The ARM variants can be built on x86_64 hardware using multiarch/qemu-user-static
docker run --rm --privileged multiarch/qemu-user-static:register --reset
Once registered you can define the dockerfile to use with -f Dockerfile.aarch64
.
Versions
- 12.06.23: - Rebase to Alpine 3.18, deprecate armhf. As announced here
- 05.03.23: - Rebase to Alpine 3.17.
- 18.10.22: - Fix wrong behavior of password/passwordless sudo
- 11.10.22: - Rebase to Alpine 3.16, migrate to s6v3.
- 15.09.22: - add netcat-openbsd with support for proxies.
- 18.07.22: - Fix service perms to comply with upgrade to s6 v3.
- 16.04.22: - Rebase to alpine 3.15.
- 16.11.21: - Add PUBLIC_KEY_URL option
- 28.06.21: - Rebasing to alpine 3.14. Add support for PAM.
- 10.02.21: - Rebasing to alpine 3.13. Add openssh-client for scp.
- 21.10.20: - Implement s6-log for openssh, which adds local timestamps to logs and can be used with a log parser like fail2ban.
- 20.10.20: - Set umask for sftp.
- 01.06.20: - Rebasing to alpine 3.12.
- 18.01.20: - Add key generation script.
- 13.01.20: - Add openssh-sftp-server.
- 19.12.19: - Rebasing to alpine 3.11.
- 17.10.19: - Initial Release.