Obnam docker image

This docker image contains the backup tool Obnam v1.21.

You can find it here:

• GitHub: maxhq/docker-obnam
• Docker Hub: maxhq/obnam

It is a modification of vdemeester/obnam with less magic, an option to set custom arguments and a bit more docs).

Default usage

By default, the image will run obnam binary and backup /source to /dest (directories inside Docker container):

$ docker run --rm \
  -v <SOURCE>:/source:ro \
  -v <DEST>:/dest \
  maxhq/obnam

... executes the following command inside the Docker container:

$ obnam backup /source /dest
# Effectively this means:
# obnam backup <SOURCE> <DEST>

You have to replace <SOURCE> and <DEST> with your real host directories!

Customization

If any arguments are given to the Docker container, those are passed on to obnam 1:1 and no magic takes place:

Example 1: version

$ docker run maxhq/obnam --version
1.19.1

Example 2: list keys

$ docker run --rm \
  -v <DEST>:/dest \
  maxhq/obnam list-keys -r /dest

... executes the following command inside the Docker container:

$ obnam list-keys -r /dest
# Effectively this means:
# obnam list-keys -r <DEST>

Usage

Configuration file

Example: you created an Obnam config file on your Docker host at /home/tux/myobnam.cfg. Obnam (in the container) searches several places for config files, firstly /etc/obnam.conf. So the easiest way to pass your config is:

$ docker run --rm \
  -v /home/tux/myobnam.cfg:/etc/obnam.conf:ro \
  ...

Local destination

Your Host filesystem:

• Source: /home/tux/Documents
• Target: /mnt/mycloud

You have to tell Docker to mount these source and destination host directories to /source and /dest respectively inside the Docker container. Let's mount the source as read-only to be sure it does not get messed up.

$ docker run --rm \
  -v /home/tux/Documents:/source:ro \
  -v /mnt/mycloud:/dest \
  maxhq/obnam

Remote (SFTP) destination

To backup to an sftp target, we will need to customize the obnam call, preventing all magic and mount:

• ~/Documents to /source
• ~/.ssh/ to /root/.ssh/ (to be able to use ssh keys)

$ docker run --rm --ti \
  -v ~/Documents:/source:ro \
  -v ~/.ssh/:/root/.ssh/:ro \
  maxhq/obnam backup -r sftp://backup.host/backup/destination /source

Encryption using GnuPG

To use GPG keys for encryption, they have to made available to the Docker container.

Let's say you set up this ~/myobnam.conf on your host:

[config]
repository = /dest
client-name = sigurd
one-file-system = 1
encrypt-with = ABCD1234
exclude = \.HIDDEN
lru-size = 1024
upload-queue-size = 512

Now just mount:

• ~/myobnam.conf to /etc/obnam.conf
• ~/.gnupg to /root/.gnupg

like this:

$ docker run --rm -ti \
  -v /home/tux/Documents:/source:ro \
  -v ~/myobnam.conf:/etc/obnam.conf:ro \
  -v ~/.gnupg:/root/.gnupg:ro \
  maxhq/obnam backup -r sftp://backup.host/backup/destination /source