astacus

Astacus is a clustered database backup system that is meant to work with multiple open-source cluster databases, such as M3 and Apache Cassandra.

My name is Maximus Backupus Astacus, Co-ordinator of the Backups of the Cluster, Master of the Storage Availability, loyal servant to the true emperor, Prunus Aivenius. Father to a failed backup, husband to a corrupted data. And I will have my restore, in this runtime or the next.

Goals

• Support multiple clustered database products

• Most of the code generic

• Product-specific code with simple, testable API

• Complexities to deal with e.g. reuse of blobs with same value in the shared code

  • It is needed to accomplish e.g. fast non-incremental M3 backups that are essentially incremental as only commit logs change frequently

• Support list of object storage backup site locations -> Facilitate migration from old to new during service cloud migration

• Have most of the code covered by unit tests

See also

• Design overview
• Implementation overview

Installation

Please see Dockerfile.fedora and Dockerfile.ubuntu for concrete up-to-date examples, but here are the current ones:

Optional features

• cassandra can be added with 'cassandra' optional:

sudo pip3 install -e '.[cassandra]'

Fedora 34

(as root or user with sudo access; for root, skip sudo prefix)

sudo dnf install -y make
make build-dep-fedora
sudo python3 ./setup.py install

Ubuntu 20.04

(as root or user with sudo access; for root, skip sudo prefix)

sudo apt-get update
sudo apt-get install -y make sudo
make build-dep-ubuntu
sudo python3 ./setup.py install

Configuration

Create astacus.conf, which specifies which database to back up, and where. The configuration file format is YAML, but as it is JSON superset, JSON is also fine.

Unfortunately the configuration part is not particularly well documented at this time, but there are some examples of file backups to local directory (JSON), local directory (YAML), Amazon S3, or Google GCS. There is even one example of backing up M3 to GCS.

Usage

Start the nodes

Start astacus server on all nodes to be backed up, either by hand or via e.g. systemd:

astacus server -c <path to configuration file>

Perform backups

Periodically (e.g. from cron) call on (ideally only one node, but it doesn't really matter as only one operation can run at a time):

• astacus backup or
• HTTP POST to http://server-address:5515/backup

Restore backups

Backup can be restored with either

• astacus restore or
• HTTP POST to http://server-address:5515/restore

List backups

To see list of backups:

• astacus list or
• HTTP GET http://server-address:5515/list

Clean up old backups

To clean up backups based on the configured retention policy,

• use astacus cleanup (from cronjob or CLI), or
• HTTP POST to http://server-address:5515/cleanup

TODO

There is separate TODO file which tracks what is still to be done.