README

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+# bsnap
+
+Manage snapshots for backups using LVM or btrfs. This is intended for use with [borg](https://www.borgbackup.org) or [rsync](https://rsync.samba.org).
+
+## Usage
+
+Running `bsnap on` will do the following:
+- Create a new directory `/a` where the snapshots will be mounted.
+- Take snapshots as configured in your `/etc/fstab`.
+- Mount the snapshots into `/a`.
+
+At this point you can run something like [borg](https://www.borgbackup.org) or [rsync](https://rsync.samba.org) on `/a` to create your backup. Once that's completed you then run `bsnap off` to unmount, remove the snapshots and cleanup `/a`.
+
+You must configure your `/etc/fstab` by setting the second last column for each entry:
+- `0` -- no snapshot will be taken and the filesystem will not be mounted into `/a`
+- `1` -- no snapshot will be taken but the filesystem will be bind mounted into `/a`
+- `2` -- a snapshot will be taken and the snapshot will be mounted into `/a`
+
+```
+# Snapshot the LVM root filesystem
+/dev/mapper/vg-root  /      ext4  defaults  2 0
+
+# Mount it into /a so it's included in the backup without snapshotting it
+UUID="ABCD-1234"     /boot  vfat  defaults  1 0
+```