Avant toute chose, il faut avoir installé Borg et initialisé un repository.

Plusieurs solutions pour l'installation, de pip3 à l'utilisation des dépôts de la distribution. Pour ma part, j'ai installé via les dépôts, sur une Debian 10 Buster :

root@debian:~# apt search borgbackup
borgbackup/stable 1.1.9-2 amd64
  deduplicating and compressing backup program
(...)
borgmatic/stable 1.2.11-1 amd64
  automatically create, prune and verify backups with borgbackup
 
root@debian:~# apt install borgbackup borgmatic

root@debian:~# generate-borgmatic-config 
Generated a sample configuration file at /etc/borgmatic/config.yaml.
 
Please edit the file to suit your needs. The values are just representative.
All fields are optional except where indicated.
 
If you ever need help: https://torsion.org/borgmatic/#issues

Il y a pas mal de commentaires dans la configuration générée. Je les ai retiré pour mettre la configuration ici.

root@debian:~# grep -v "#" /etc/borgmatic/config.yaml 
 
location:
    source_directories:
        - /home
        - /etc
        - /data
        - /var/log/syslog*
    repositories:
        - serveurA@serveurB:/mnt/data/backups/serveurA
 
storage:
    encryption_passphrase: "maGrossePassPhrase"
    checkpoint_interval: 1800
    compression: lz4
 
retention:
    keep_hourly: 24
    keep_daily: 7
    keep_weekly: 4
    keep_monthly: 6
 
consistency:
    checks:
        - repository
        - archives

root@debian:~# borgmatic -l
root@debian:~# borgmatic --list
debian-2019-07-29T12:36:07.775077    Mon, 2019-07-29 12:36:13 [785df6754aaf22946e21b09126bbfffe61f3f07ede975fc648e637a636b1e0d8]

root@debian:~# borgmatic -i
root@debian:~# borgmatic --info
Repository ID: afc0842fce13772d306b45df8643fdc2741a0c27056f30584a65084ca192c979
Location: ssh://serveurA@serveurB/mnt/data/backups/serveurA
Encrypted: Yes (repokey BLAKE2b)
Cache: /root/.cache/borg/afc0842fce13772d306b45df8643fdc2741a0c27056f30584a65084ca192c979
Security dir: /root/.config/borg/security/afc0842fce13772d306b45df8643fdc2741a0c27056f30584a65084ca192c979
------------------------------------------------------------------------------
                       Original size      Compressed size    Deduplicated size
All archives:                2.25 MB            950.02 kB            938.77 kB
 
                       Unique chunks         Total chunks
Chunk index:                     503                  522

root@debian:~# crontab -l
0 3 * * * /usr/bin/borgmatic

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