Docs site (#269)

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docs/how-tos/replace-deprecated-backup-from-snapshot.md

@@ -0,0 +1,37 @@
+---
+title: Replace deprecated BACKUP_FROM_SNAPSHOT usage
+layout: default
+parent: How Tos
+nav_order: 16
+---
+
+# Replace deprecated `BACKUP_FROM_SNAPSHOT` usage
+
+Starting with version 2.15.0, the `BACKUP_FROM_SNAPSHOT` feature has been deprecated.
+If you need to prepare your sources before the backup is taken, use `archive-pre`, `archive-post` and an intermediate volume:
+
+```yml
+version: '3'
+
+services:
+  my_app:
+    build: .
+    volumes:
+      - data:/var/my_app
+      - backup:/tmp/backup
+    labels:
+      - docker-volume-backup.archive-pre=cp -r /var/my_app /tmp/backup/my-app
+      - docker-volume-backup.archive-post=rm -rf /tmp/backup/my-app
+
+  backup:
+    image: offen/docker-volume-backup:v2
+    environment:
+      BACKUP_SOURCES: /tmp/backup
+    volumes:
+      - backup:/backup:ro
+      - /var/run/docker.sock:/var/run/docker.sock:ro
+
+volumes:
+  data:
+  backup:
+```