matrix-docker-ansible-deploy/docs/configuring-playbook-backup-borg.md

Setting up borg backup (optional)

The playbook can install and configure borgbackup with borgmatic for you. BorgBackup is a deduplicating backup program with optional compression and encryption. That means your daily incremental backups can be stored in a fraction of the space and is safe whether you store it at home or on a cloud service.

The backup will run based on matrix_backup_borg_schedule var (systemd timer calendar), default: 4am every day

Prerequisites

1. Create ssh key on any machine:

ssh-keygen -t ed25519 -N '' -f matrix-borg-backup -C matrix

2. Add public part of that ssh key to your borg provider / server:

# example to append the new PUBKEY contents, where:
# PUBKEY is path to the public key,
# USER is a ssh user on a provider / server
# HOST is a ssh host of a provider / server
cat PUBKEY | ssh USER@HOST 'dd of=.ssh/authorized_keys oflag=append conv=notrunc'

Adjusting the playbook configuration

Minimal working configuration (inventory/host_vars/matrix.DOMAIN/vars.yml) to enable borg backup:

matrix_backup_borg_enabled: true
matrix_backup_borg_location_repositories:
 - USER@HOST:REPO
matrix_backup_borg_storage_encryption_passphrase: "PASSPHRASE"
matrix_backup_borg_ssh_key_private: |
	PRIVATE KEY

where:

• USER - ssh user of a provider / server
• HOST - ssh host of a provider / server
• REPO - borg repository name, it will be initialized on backup start, eg: matrix
• PASSPHRASE - super-secret borg passphrase, you may generate it with pwgen -s 64 1 or use any password manager
• PRIVATE KEY - the content of the public part of the ssh key you created before

Check the roles/matrix-backup-borg/defaults/main.yml for the full list of available options

Installing

After configuring the playbook, run the installation command again:

ansible-playbook -i inventory/hosts setup.yml --tags=setup-all,start