[![GitHub release](https://img.shields.io/github/release/Antynea/grub-btrfs.svg)](https://github.com/Antynea/grub-btrfs/releases)
![](https://img.shields.io/github/license/Antynea/grub-btrfs.svg)

## grub-btrfs 

[![GitHub release](https://img.shields.io/github/release/Antynea/grub-btrfs.svg)](https://github.com/Antynea/grub-btrfs/releases)
![](https://img.shields.io/github/license/Antynea/grub-btrfs.svg)

## grub-btrfs 

##### BTC donation address: `1Lbvz244WA8xbpHek9W2Y12cakM6rDe5Rt`
- - -
### Description:
Improves grub by adding "btrfs snapshots" to the grub menu.

You can boot your system on a "snapshot" from the grub menu.  
Supports manual snapshots, snapper, timeshift ...

##### Warning: booting on read-only snapshots can be tricky

If you choose to do it, `/var/log` or even `/var` must be on a separate subvolume.  
Otherwise, make sure your snapshots are writeable.  
See [this ticket](https://github.com/Antynea/grub-btrfs/issues/92) for more info.

This project includes its own solution.  
Refer to the [documentation](https://github.com/Antynea/grub-btrfs/blob/master/initramfs/readme.md).

- - -
### What features does grub-btrfs have?
* Automatically list snapshots existing on root partition (btrfs).
* Automatically detect if `/boot` is in separate partition.
* Automatically detect kernel, initramfs and intel/amd microcode in `/boot` directory on snapshots.
* Automatically create corresponding "menuentry" in `grub.cfg`
* Automatically detect the type/tags and descriptions/comments of snapper/timeshift snapshots.
* Automatically generate `grub.cfg` if you use the provided systemd service.

- - -
### Installation:
#### Arch Linux
The package is available in the community repository [grub-btrfs](https://archlinux.org/packages/community/any/grub-btrfs/)
```
pacman -S grub-btrfs
```

#### Gentoo
grub-btrfs is only available in the Gentoo User Repository (GURU) and not in the official Gentoo repository.  
If you have not activated the GURU yet, do so by running:
```
emerge -av app-eselect/eselect-repository 
eselect repository enable guru 
emerge --sync 
```


Now merge grub-btrfs via 
`emerge app-backup/grub-btrfs`

If you are using SystemD on Gentoo, make sure the USE-Flag `systemD` is set. (Either globally in make.conf or in package.use for the package app-backup/grub-btrfs)
Without systemD USE-Flag the OpenRC-Daemon of grub-btrfs will be installed.

#### Kali Linux
[grub-btrfs](http://pkg.kali.org/pkg/grub-btrfs) is available in the Kali Linux repository and can be installed with:  
```
apt install grub-btrfs
```
Booting into read-only snapshots is fully supported when choosing "btrfs" as file system during a standard Kali Linux installation following [this walk-through](https://www.kali.org/docs/installation/btrfs/).  

#### Manual
* Run `make install` or look into Makefile for instructions on where to put each file.
* Run `make help` to check what options are available. 
* Dependencies:
  * [btrfs-progs](https://archlinux.org/packages/core/x86_64/btrfs-progs/)
  * [grub](https://archlinux.org/packages/core/x86_64/grub/)
  * [bash >4](https://archlinux.org/packages/core/x86_64/bash/)
  * [gawk](https://archlinux.org/packages/core/x86_64/gawk/)

#### NOTE: All distros
Generate your grub menu after installation for the changes to take effect.  
For example:  
On **Arch Linux** or **Gentoo** use `grub-mkconfig -o /boot/grub/grub.cfg`.  
On **Fedora** use `grub2-mkconfig -o /boot/grub2/grub.cfg`  
On **Debian-like** distribution `update-grub` is an alias to `grub-mkconfig ...`
- - -
### Customization:

You have the possibility to modify many parameters in `/etc/default/grub-btrfs/config`.  
See [config file](https://github.com/Antynea/grub-btrfs/blob/master/config) for more information.

- - -
### Automatically update grub upon snapshot:
To automatically regenerate `grub-btrfs.cfg` when a modification appears in the `/.snapshots` mount point, run
```bash
systemctl enable grub-btrfs.path
systemctl start grub-btrfs.path  # In case the mount point is available already
```
Monitoring starts automatically when the mount point becomes available.
    
#### Snapshots not in `/.snapshots`
To modify `grub-btrfs.path` run
```bash
systemctl edit --full grub-btrfs.path
systemctl reenable grub-btrfs.path
```
To find out the name of the `.mount` unit use `systemctl list-units -t mount`.

**Timeshift**
1. Run `systemctl edit --full grub-btrfs.path`
1. Replace the whole block by:
```
[Unit]
Description=Monitors for new snapshots
DefaultDependencies=no
Requires=run-timeshift-backup.mount
After=run-timeshift-backup.mount
BindsTo=run-timeshift-backup.mount

[Path]
PathModified=/run/timeshift/backup/timeshift-btrfs/snapshots

[Install]
WantedBy=run-timeshift-backup.mount
```
1. Run `systemctl reenable grub-btrfs.path` to reload the changes you made

1. Run `systemctl start grub-btrfs.path` to start monitoring.<br>Otherwise, the unit will automatically start monitoring when the mount point will be available.  

Note:
You can view your change to `systemctl cat grub-btrfs.path`.
To revert change use `systemctl revert grub-btrfs.path`.

----
### Automatically update grub upon restart/boot:
[Look at this comment](https://github.com/Antynea/grub-btrfs/issues/138#issuecomment-766918328)  
Currently not implemented

##
#### OpenRC
1. If you would like grub-btrfs menu to automatically update when a snapshot is created or deleted:
* If you are using Timeshift, newer versions of it mount their snapshots to `/run/timeshift/$pidofthecurrentlyrunnigtimeshift/backup/timeshift-btrfs`. The OpenRC-Daemon can automatically take care of the detection of the correct PID and directory if you set the variable `timeshift_auto` to `true` in `etc/conf.d/grub-btrfsd`. In this case the variable `snapshots` has no influence.
* If you don't want to use `timeshift_auto`, set the variable `snapshots` in the file `/etc/conf.d/grub-btrfsd` to the path of your snapshot directory. By default this is set to snappers default directory,  `./snapper`.
For Timeshift keep in mind, that newer versions of Timeshift will not work with the `/run/timeshift/backup/timeshift-btrfs/snapshots` path. However there is a [workaround](https://www.lorenzobettini.it/2022/07/timeshift-and-grub-btrfs-in-linux-arch/) that works for now. 
* Use `rc-config add grub-btrfsd default`, to start the grub-btrfsd daemon the next time the system boots. 
	* To start `grub-btrfsd` right now, run `rc-service grub-btrfsd start`
	* `grub-btrfsd` automatically watches the snapshot directory and updates the grub-menu when a change occurs

2. If you would like grub-btrfs menu to automatically update on system restart/ shutdown:
Just add the following script as `/etc/local.d/grub-btrfs-update.stop`
	```bash
	#!/bin/bash
	
	description="Update the grub btrfs snapshots menu"
	name="grub-btrfs-update"
	
	depend()
	{
	  use localmount
	}
	
	bash -c 'if [ -s "${GRUB_BTRFS_GRUB_DIRNAME:-/boot/grub}/grub-btrfs.cfg" ]; then /etc/grub.d/41_snapshots-btrfs; else {GRUB_BTRFS_MKCONFIG:-grub-mkconfig} -o {GRUB_BTRFS_GRUB_DIRNAME:-/boot/grub}/grub.cfg; fi' 
	```
	
	Make your script executable with `chmod a+x /etc/local.d/grub-btrfs-update.stop`.

* The extension ".stop" at the end of the filename indicates to locald that this script should be run at shutdown. 
 If you want to run the menu update on startup instead, rename the file to `grub-btrfs-update.start`
* Works for snapper and timeshift

##### Warning:
by default, `grub-mkconfig` command is used.  
Might be `grub2-mkconfig` on some systems (Fedora ...).   
Edit `GRUB_BTRFS_MKCONFIG` variable in `/etc/default/grub-btrfs/config` file to reflect this.
- - -
### Special thanks for assistance and contributions
* [Maxim Baz](https://github.com/maximbaz)
* [Schievel1](https://github.com/Antynea/grub-btrfs/discussions/173#discussioncomment-1438790)
* [All contributors](https://github.com/Antynea/grub-btrfs/graphs/contributors)
- - -