Debian based container image, running openssh-daemon only accessable by user named "borg" using SSH-Publickey Auth & "borgbackup" as client. Backup-Repositoriees, client's SSH-Keys & SSHd's Hostkeys will be stored in persistent storage. For every ssh-key added, a own borg-repository will be created.
NOTE: I will assume that you know, what a ssh-key is and how to generate & use it. If not, you might want to start here: Arch Wiki
Here is a quick example how to configure & run this image:
$ mkdir -p borg/sshkeys/clients
Make sure that the permissions are right on the sshkey folder:
$ chown 1000:1000 borg/sshkeys
Remember: Filename = Borg-repository name!
$ cp ~/.ssh/my_machine.pub borg/sshkeys/clients/my_machine
The OpenSSH-Deamon will expose on port 22/tcp - so you will most likely want to redirect it to a different port. Like in this example:
docker run -td \
-p 2222:22 \
--volume ./borg/sshkeys:/sshkeys \
--volume ./borg/backup:/backup \
nold360/borgserver:latest
- Place Borg-Clients SSH-PublicKeys in persistent storage
- Client Repositories will be named by the filename found in /sshkeys/clients/
Use this variable if you want to set special options for the "borg serve"-command, which is used internally.
See the the documentation for all available arguments: borgbackup.readthedocs.io
docker run -e BORG_SERVE_ARGS="--append-only --debug" (...) nold360/borgserver
We will need two persistent storage directories for our borgserver to be usefull.
This directory has two subdirectories:
Here we will put all SSH public keys from our borg clients, we want to backup. Every key must be it's own file, containing only one line, with the key. The name of the file will become the name of the borg repository, we need for our client to connect.
That means every client get's it's own repository. So you might want to use the hostname of the client as the name of the sshkey file.
F.e. /sshkeys/clients/webserver.mydomain.com
Than your client would have to initiat the borg repository like this:
webserver.mydomain.com ~$ borg init ssh://borg@borgserver-container/backup/webserver.mydomain.com/my_first_repo
!IMPORTANT!: The container wouldn't start the SSH-Deamon until there is at least one ssh-keyfile in this directory!
This directory will be automaticly created on first start. Also run.sh will copy the SSH-Hostkeys here, so your clients can verify it's borgservers ssh-hostkey.
In this directory will borg write all the client data to. It's best to start with an empty directory.
Here is a quick example, how to run borgserver using docker-compose:
services:
borgserver:
image: nold360/borgserver
volumes:
- /backup:/backup
- ./sshkeys:/sshkeys
ports:
- "2222:22"
environment:
BORG_SERVE_ARGS: "--append-only"
With this configuration (on your borg client) you can easily connect to your borgserver.
Host backup
Hostname my.docker.host
Port 2222
User borg
Now initiate a borg-repository like this:
$ borg init backup:my_first_borg_repo
And create your first backup!
$ borg create backup:my_first_borg_repo::documents-2017-11-01 /home/user/MyImportentDocs