Add documentation on how to make backups redundant with multiple repositories.

NEWS

@@ -2,6 +2,8 @@
  * #339: Fix for intermittent timing-related test failure of logging function.
  * Clarify database documentation about excluding named pipes and character/block devices to prevent
    hangs.
+ * Add documentation on how to make backups redundant with multiple repositories:
+   https://torsion.org/borgmatic/docs/how-to/make-backups-redundant/
 
 1.5.8
  * #336: Fix for traceback when running Cronitor, Cronhub, and PagerDuty monitor hooks.

README.md

@@ -75,6 +75,7 @@ borgmatic is powered by [Borg Backup](https://www.borgbackup.org/).
 
  * [Set up backups with borgmatic](https://torsion.org/borgmatic/docs/how-to/set-up-backups/) ⬅ *Start here!*
  * [Make per-application backups](https://torsion.org/borgmatic/docs/how-to/make-per-application-backups/)
+ * [Make backups redundant](https://torsion.org/borgmatic/docs/how-to/make-backups-redundant/)
  * [Deal with very large backups](https://torsion.org/borgmatic/docs/how-to/deal-with-very-large-backups/)
  * [Inspect your backups](https://torsion.org/borgmatic/docs/how-to/inspect-your-backups/)
  * [Monitor your backups](https://torsion.org/borgmatic/docs/how-to/monitor-your-backups/)

docs/how-to/backup-to-a-removable-drive-or-an-intermittent-server.md

@@ -103,5 +103,6 @@ There are some caveats you should be aware of with this feature.
 
  * [Set up backups with borgmatic](https://torsion.org/borgmatic/docs/how-to/set-up-backups/)
  * [Make per-application backups](https://torsion.org/borgmatic/docs/how-to/make-per-application-backups/)
+ * [Make backups redundant](https://torsion.org/borgmatic/docs/how-to/make-backups-redundant/)
  * [Add preparation and cleanup steps to backups](https://torsion.org/borgmatic/docs/how-to/add-preparation-and-cleanup-steps-to-backups/)
  * [Monitor your backups](https://torsion.org/borgmatic/docs/how-to/monitor-your-backups/)

docs/how-to/make-backups-redundant.md

@@ -0,0 +1,47 @@
+---
+title: How to make backups redundant
+---
+## Multiple repositories
+
+If you really care about your data, you probably want more than one backup of
+it. borgmatic supports this in its configuration by specifying multiple backup
+repositories. Here's an example:
+
+```yaml
+location:
+    # List of source directories to backup.
+    source_directories:
+        - /home
+        - /etc
+
+    # Paths of local or remote repositories to backup to.
+    repositories:
+        - 1234@usw-s001.rsync.net:backups.borg
+        - k8pDxu32@k8pDxu32.repo.borgbase.com:repo
+        - /var/lib/backups/local.borg
+```
+
+When you run borgmatic with this configuration, it invokes Borg once for each
+configured repository in sequence. (So, not in parallel.) That means—in each
+repository—borgmatic creates a single new backup archive containing all of
+your source directories.
+
+Here's a way of visualizing what borgmatic does with the above configuration:
+
+1. Backup `/home` and `/etc` to `1234@usw-s001.rsync.net:backups.borg`
+2. Backup `/home` and `/etc` to `k8pDxu32@k8pDxu32.repo.borgbase.com:repo`
+3. Backup `/home` and `/etc` to `/var/lib/backups/local.borg`
+
+This gives you redundancy of your data across repositories and even
+potentially across providers.
+
+See [Borg repository URLs
+documentation](https://borgbackup.readthedocs.io/en/stable/usage/general.html#repository-urls)
+for more information on how to specify local and remote repository paths.
+
+
+## Related documentation
+
+ * [Set up backups with borgmatic](https://torsion.org/borgmatic/docs/how-to/set-up-backups/)
+ * [Make per-application backups](https://torsion.org/borgmatic/docs/how-to/make-per-application-backups/)
+ * [Backup to a removable drive or an intermittent server](https://torsion.org/borgmatic/docs/how-to/backup-to-a-removable-drive-or-an-intermittent-server/)

docs/how-to/make-per-application-backups.md

@@ -153,3 +153,4 @@ that your shell may interpret.
 ## Related documentation
 
  * [Set up backups with borgmatic](https://torsion.org/borgmatic/docs/how-to/set-up-backups/)
+ * [Make backups redundant](https://torsion.org/borgmatic/docs/how-to/make-backups-redundant/)

docs/how-to/set-up-backups.md

@@ -150,6 +150,13 @@ FAQ](http://borgbackup.readthedocs.io/en/stable/faq.html#how-can-i-specify-the-e
 for more info.
 
 
+### Redundancy
+
+If you'd like to configure your backups to go to multiple different
+repositories, see the documentation on how to [make backups
+redundant](https://torsion.org/borgmatic/docs/how-to/make-backups-redundant/).
+
+
 ### Validation
 
 If you'd like to validate that your borgmatic configuration is valid, the
@@ -311,6 +318,7 @@ it.
 ## Related documentation
 
  * [Make per-application backups](https://torsion.org/borgmatic/docs/how-to/make-per-application-backups/)
+ * [Make backups redundant](https://torsion.org/borgmatic/docs/how-to/make-backups-redundant/)
  * [Deal with very large backups](https://torsion.org/borgmatic/docs/how-to/deal-with-very-large-backups/)
  * [Inspect your backups](https://torsion.org/borgmatic/docs/how-to/inspect-your-backups/)
  * [Monitor your backups](https://torsion.org/borgmatic/docs/how-to/monitor-your-backups/)