March 3, 2020

Backups with restic and rclone
Encrypted local and cloud backups

I have started using restic backup about 2 years ago. I have learned recently, that some of my colleagues are not aware of its existence or not aware of tight integration with rclone. These two are a powerful combo, allowing for encrypted local and cloud backups with easy.

I also needed to recover from backups multiple times already, so even this part of backup strategy is working :)

Restic

Restic is super easy to use. It is secure as it assumes that storage of the backup is untrusted by default. Backups are encrypted with AES-256 in counter mode and authentication is done using Poly1305-AES. Checkout Filippo’s article for a deeper look into the restic security model. It is quite fast. Restic needs under 4 minutes to go through my 366GB home. rsync needed something like 20-30 minutes to do the same job.

I am using restic with two storage backends – sftp and rclone. Mode of operation is still the same, only what changes (from the user’s perspective is URL).

Getting started

After you install restic, you need to initialize your storage repository. It is as simple as:

~ ❯ restic -r sftp:bobek@klobouk:/klobouk/backups/restic init
enter password for new repository: 
enter password again: 
created restic repository 0507dc2c01 at sftp:bobek@klobouk:/klobouk/backups/restic

Please note that knowledge of your password is required to access
the repository. Losing your password means that your data is
irrecoverably lost.

Where sftp:bobek@klobouk:/klobouk/backups/restic is a repository URL. As you would guess

  • sftp is a protocol to be used (sftp in this case)
  • bobek is a username used for establishing connection
  • klobouk is a server name (ip address, FQDN, alias from the ssh_config, basically anything you can ssh/sftp to)
  • /klobouk/backups/restic is the destination path for the repository on the server side

Making backup

Making a snapshot (incremental backup) is question of using backup command. You can pass additional arguments, such as -e for filtering out certain paths. Below is example of backing up my home:

~ ❯ restic -r sftp:bobek@klobouk:/klobouk/backups/restic backup -e ~/Movies ~/
Enter passphrase for key '/home/bobek/.ssh/id_rsa4096': 
enter password for repository: 
repository 0507dc2c01 opened successfully, password is correct

Files:        6941 new,  2045 changed, 2041192 unmodified
Dirs:            0 new,     1 changed,     0 unmodified
Added to the repo: 2.609 GiB

processed 2050178 files, 365.919 GiB in 3:44
snapshot 72217508 saved

You can check your snapshots with snapshots command, such as

~ ❯ restic -r sftp:bobek@klobouk:/klobouk/backups/restic snapshots                
enter password for repository:
repository 0507dc2c01 opened successfully, password is correct
ID        Time                 Host        Tags        Paths
------------------------------------------------------------------
41a3d112  2019-11-16 17:23:12  bobek                   /home/bobek
7816d840  2019-11-23 08:14:47  bobek                   /home/bobek
7788586b  2019-12-01 21:58:40  bobek                   /home/bobek
// removed bunch of lines to improve readability of the article
fda51794  2020-03-02 22:37:36  bobek                   /home/bobek
72217508  2020-03-03 09:20:54  bobek                   /home/bobek
------------------------------------------------------------------
56 snapshots

Pruning restic repository

Your backup repository will grow indefinitely as retention policy is not part of the backup command. You can use forget command for that. As you can see, I have not ran it for a while. Let’s fix that.

I am going to do it slightly differently this time and ssh to the server hosting the repository, so I will make all IO operations local (you can still use sftp:... with no problem).

bobek@klobouk:~$ restic -r /klobouk/backups/restic forget --keep-daily 7 --keep-weekly 10 --prune --cleanup-cache
enter password for repository:
repository 0507dc2c01 opened successfully, password is correct
Applying Policy: keep the last 7 daily, 10 weekly snapshots
keep 15 snapshots:
ID        Time                 Host        Tags        Reasons          Paths
-----------------------------------------------------------------------------------
cadfc8cc  2020-01-05 23:38:23  bobek                   weekly snapshot  /home/bobek
1f6bd29f  2020-01-11 22:56:46  bobek                   weekly snapshot  /home/bobek
2cfaf041  2020-01-19 20:05:58  bobek                   weekly snapshot  /home/bobek
b222742c  2020-01-26 23:59:14  bobek                   weekly snapshot  /home/bobek
0dbcbc46  2020-02-02 21:18:13  bobek                   weekly snapshot  /home/bobek
8c1ad6e8  2020-02-08 14:11:41  bobek                   weekly snapshot  /home/bobek
1794a66f  2020-02-16 23:05:10  bobek                   weekly snapshot  /home/bobek
bb3abe88  2020-02-23 23:22:54  bobek                   weekly snapshot  /home/bobek
e4f2f56c  2020-02-24 21:16:06  bobek                   daily snapshot   /home/bobek
9940a28b  2020-02-25 21:39:12  bobek                   daily snapshot   /home/bobek
df5bab63  2020-02-26 21:23:02  bobek                   daily snapshot   /home/bobek
b8d11888  2020-02-27 23:41:14  bobek                   daily snapshot   /home/bobek
272d9e5e  2020-02-28 17:19:45  bobek                   daily snapshot   /home/bobek
                                                       weekly snapshot
fda51794  2020-03-02 22:37:36  bobek                   daily snapshot   /home/bobek
72217508  2020-03-03 09:20:54  bobek                   daily snapshot   /home/bobek
                                                       weekly snapshot
-----------------------------------------------------------------------------------
15 snapshots

remove 41 snapshots:
ID        Time                 Host        Tags        Paths      
------------------------------------------------------------------
41a3d112  2019-11-16 17:23:12  bobek                   /home/bobek
7816d840  2019-11-23 08:14:47  bobek                   /home/bobek
// again, removed bunch of lines here
c8f29801  2020-03-02 07:12:00  bobek                   /home/bobek
4a7085c1  2020-03-02 21:03:36  bobek                   /home/bobek
------------------------------------------------------------------
41 snapshots
41 snapshots have been removed, running prune

You can run forget without a --prune and it will be quick as it only marks snapshots for removal. The actual removal of data and compaction of the repository can be also achieved with a separate prune command. Just be aware, that prune can take a considerable amount of time.

bobek@klobouk:~$ du -sh /klobouk/backups/restic
587G    /klobouk/backups/restic

bobek@klobouk:~$ restic -r /klobouk/backups/restic prune --cleanup-cache
enter password for repository:
repository 5a4fef57 opened successfully, password is correct
counting files in repo
building new index for repo
[1:10:38] 100.00%  121521 / 121521 packs
repository contains 121521 packs (2995676 blobs) with 577.392 GiB
processed 2995676 blobs: 0 duplicate blobs, 0 B duplicate
load all snapshots
find data that is still in use for 15 snapshots
[7:16] 100.00%  15 / 15 snapshots
found 2294461 of 2995676 data blobs still in use, removing 701215 blobs
will remove 0 invalid files
will delete 27364 packs and rewrite 14807 packs, this frees 172.604 GiB
[2:27:26] 100.00%  14807 / 14807 packs rewritten
counting files in repo
[37:10] 100.00%  85892 / 85892 packs
finding old index files
saved new indexes as [82c9a37f 5acc102a d5daaa0c 4a5dee08 881d6187 e9dfa06e 5bf9bf27 a3b85e96 daf45279 b56cc75e 95ef84d2 7e39afc3 9f10a455 ea80a8e9 b65b4106 6def21e2 c6ea3aae c0b30616 bb03b1eb f9c4261c 2babd31c e7d80fa8 8a5b5e47 984d8a78 c3275bb3 071e64a9 c97bb60c f263321e 67629707]
remove 125 old index files
[26:01] 100.00%  42171 / 42171 packs deleted
done

bobek@klobouk:~$ du -sh /klobouk/backups/restic
412G    /klobouk/backups/restic

Recovery

Let’s restore some data. Frequently, I don’t need a recovery of complete backup (like complete home), but rather some particular directory or file. Something like – I’ve just crashed my Firefox, lost all the open tabs and want to restore the complete Firefox directory.

  1. Use snapshots to figure ID of snapshot we want to recover from. Let’s pick the latest from our example, which is 72217508 at our example above.
  2. User restore to get files from that snapshot. I can look something like
~ ❯ restic -r sftp:bobek@klobouk:/klobouk/backups/restic restore 72217508  --target /tmp/restore-firefox --include /home/bobek/.mozilla/firefox
enter password for repository:
repository 0507dc2c01 opened successfully, password is correct
restoring <Snapshot 72217508 of [/home/bobek] at 2020-03-03 09:20:54.744399448 +0100 CET by bobek@bobek> to /tmp/restore

And we have our files under /tmp/restore/home/bobek/.mozilla/firefox as expected, with a proper file mode bits etc.

Locking

restic locks the repo when working with it. It will tell you when and who locked it. For example:

~ ❯ restic -r sftp:bobek@klobouk:/klobouk/backups/restic snapshots
enter password for repository:
repository 0507dc2c01 opened successfully, password is correct
Fatal: unable to create lock in backend: repository is already locked exclusively by PID 18172 on klobouk by bobek (UID 1000, GID 1000)
lock was created at 2020-03-03 09:48:29 (1h37m6.789848817s ago)
storage ID 9e313963

In cases, where you are sure that process which acquired lock is already dead, you may need to use unlock command. It is also a good idea to run restic check to verify consistency of the repository afterwards.

rclone

rclone is like rsync for cloud. It supports usual suspects (Amazon S3, Google Drive, Dropbox) but also a lot of others.

I will use Google Drive as an example. Just follow the rclone GDrive documentation to set it up. You need to pick a name for your configuration. I have used gdrive, so after everything is done, you can issues

~ ❯ rclone ls gdrive:

to list all files on your Google Drive. No need for mounting FUSE based emulations etc. Also rclone behaves like rsync and can keep two destinations in sync. So the practical use-case, is synchronization between Dropbox and GDrive:

~ ❯ rclone sync -P "dropbox:/Apps/Pragmatic Bookshelf/" "gdrive:/Pragmatic Bookshelf/"

restic with rclone

Finally – let’s setup backup to the cloud. And it is simple as:

  • configuring rclone for the cloud storage of your choice (gdrive in my case)
  • using rclone backend of the restic to talk to the selected storage, for example:

    ~ ❯ restic -r rclone:gdrive:restic init
    

    which will create restic folder at your gdrive.

  • and using all the restic commands we have covered before, like

    ~ ❯   restic -r rclone:gdrive:restic backup -e .notmuch ~/Mail
    

    to backup your ~/Mail folder to GDrive.

Regular backups

Backups are useful only if you do them regularly. I have initially place restic to my crontab to schedule backups. But ended up with running backups manually after all as I need to have it under a bit more control. Thus I have a script which I run before getting to bed:

#!/bin/bash
set -e

SFTP_REPO="sftp:bobek@10.0.0.250:/klobouk/backups/restic"
GDRIVE_REPO="rclone:gdrive:restic"

for i in "$@"
do
  case $i in
      --prune)
      RESTIC_PRUNE=true
      ;;
      *)
              # unknown option
      ;;
  esac
done

ssh root@10.0.0.250 'df -h /klobouk/'

read -s -t 5 -p "Enter restic password, followed by [ENTER]" RESTIC_PASSWORD && export RESTIC_PASSWORD
echo ""

restic -r "$SFTP_REPO" snapshots --cleanup-cache

if [[ ("$RESTIC_PRUNE" = true) ]]
then
  restic -r "$GDRIVE_REPO" forget --keep-daily 14 --keep-weekly 18 --prune --cleanup-cache
  restic -r "$GDRIVE_REPO" check

  restic -r "$SFTP_REPO" forget --keep-daily 7 --keep-weekly 10 --prune --cleanup-cache
  restic -r "$SFTP_REPO" check
fi

rclone sync -P "dropbox:/Apps/Pragmatic Bookshelf/" "gdrive:/Pragmatic Bookshelf/"
restic -r "$GDRIVE_REPO" backup -e .notmuch ~/Mail
restic -r "$SFTP_REPO" backup -e ~/Movies ~/

sudo poweroff