Juju Backup All

Introduction

The juju-backup-all snap allows operators to streamline backing up their models in one go.

While various charms offer backup capabilities, it is up to the operator to determine which charms
do so and how to invoke said capability. The juju-backup-all snap simplifies this down to a single
command: juju-backup-all.

It currently supports backing up juju controllers, juju configs, and the following charms:

• MySQL Innodb Cluster
• PostgreSQL
• etcd

This snap enumerates through all controllers, backing up the controller and scanning through each
model for any applications that can be backed up. It then saves these backups.

Find it on the Snap Store!

Installation

Install juju-backup-all from Snap Store with:

snap install juju-backup-all

Then, make sure the appropriate interfaces are plugged:

snap connect juju-backup-all:juju-client-observe
snap connect juju-backup-all:ssh-keys

Usage

This tool primarily auto-discovers controllers/charms that need backing up. To backup the current
controller, simply run:

juju-backup-all

This will backup all apps of all models (in the current controller) of supported charms and output
them into juju-backups/ directory. It will also backup the local juju client config.

For a more complex command, here's an example that specifies an output directory, excludes certain
charms, excludes the juju client config backup, and runs backups on all controllers.

juju-backup-all -o my/backups/ \
  -e postgresql \
  -e etcd \
  --all-controllers

If the charm cannot perform backup because the disk on the unit is full, or the
default backup base directory is not writable for any reason. You can change the
backup base directory for the unit. Directories will be created if needed.

Currently, the following applications are supported with the those default
values.

juju-backup-all \
  --backup-location-on-postgresql "/home/ubuntu" \
  --backup-location-on-mysql "/var/backups/mysql" \
  --backup-location-on-etcd "/home/ubuntu/etcd-snapshots" \

The following command will give all the possible arguments that can be passed to the tool:

juju-backup-all -h

The backup directory structure will look like the following:

juju-backups/
├── local_configs/
│   └── juju.tar.gz
├── controller1/
│   ├── model1/
│   │   ├── mysql-innodb-cluster/
│          └── mysqldump.tar.gz
└── controller2/
    └── model1/
        └── etcd-app/
            └── backups.tar.gz

Development and Testing

Functional tests

To run functional tests:

tox -e func

Several environment variables are available for setting to help expedite testing.
These include:

• PYTEST_KEEP_MODELS: keeps the models after running functional tests. This helps in debugging and reuse of models
  for quicker testing
• PYTEST_MYSQL_MODEL, PYTEST_ETCD_MODEL: setting these to a current model will have the functional tests use
  that model instead of deploying another one.
• JUJU_DATA: Specify where your juju client config directory is located. If not set, it will default to
  ~/.local/share/juju. This is needed in functional testing as the tool runs some subprocess juju commands
  (like juju create-backup) and without this set, the environment for functional tests has no info on controllers.
• PYTEST_SELECT_TESTS: use to select tests based on their name (via
  pytest -k expression docs)

Unit tests

The unit tests run for two different versions of python - 3.6 (Ubuntu Bionic) and 3.8 (Ubuntu Focal), they will have to be available
to run the unit tests.

To run unit tests:

tox -e unit

To run unit tests and also generate html coverage reports:

tox -e unit
tox -e cover

Building and Installing Snap Locally

To build the snap locally, simply run:

snapcraft --use-lxd

You can then install the locally built snap with:

sudo snap install --dangerous ./juju-backup-all_${VERSION}.snap

To clean up the snapcraft build environment, run the following:

snapcraft clean --use-lxd