backup host -> backup1

backup1/README.md

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+# Generic Backup Host
+
+## Crontab
+
+Runs on the second of every month.
+
+```
+0 0 2 * * cd /home/USER/backups && bash prune.sh
+```
+
+## Filename Pattern
+
+Container volume backups are of the format:
+
+```
+gitea-data-2023-06-17_050002.tar.gz.enc
+^          ^                ^
+|          |                Backups are encrypted tarballs
+|          |
+|          ISO Datetime separated by _
+|
+Container volume name (*-data)
+```
+
+Regex to match backups that are *not* from the first of every month, using the above format:
+
+```
+[0-9A-Za-z]+-data-[0-9]{4}-[0-9]{2}-([^0][0-9]|[0-9][^1])_.*
+```
+

backup1/prune.sh

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+#!/usr/bin/bash
+
+# Prunes container data folders monthly on backup host.
+# Removes all items but the backup from the first day of the month.
+# Should run on the first day of every month - since it doesn't remove the backup
+# from that time, it doesn't matter what time it's run
+
+for item in *; do
+    if [[ "$item" =~ [0-9A-Za-z]+-data-[0-9]{4}-[0-9]{2}-([^0][0-9]|[0-9][^1])_.* ]]; then
+        echo "Removing $item"
+        rm -f $item
+    fi
+done
+