22 KiB
Thanks for using restic. This document will give you an overview of the basic functionality provided by restic.
Building/installing restic
If you are using Mac OS X, you can install restic using the homebrew packet manager:
$ brew tap restic/restic
$ brew install restic
On archlinux, there is a package called restic-git which can be installed from AUR, e.g. with pacaur:
$ pacaur -S restic-git
At debian stable you can install 'go' directly from the repositories (as root):
$ apt-get install golang-go
after installation of 'go' go straight forward to 'git clone [...]'
If you are using Linux, BSD or Windows, the only way to install restic on your system right now is to compile it from source. restic is written in the Go programming language and you need at least Go version 1.6. Building restic may also work with older versions of Go, but that's not supported. See the Getting started guide of the Go project for instructions how to install Go.
In order to build restic from source, execute the following steps:
$ git clone https://github.com/restic/restic
[...]
$ cd restic
$ go run build.go
At the moment, the only tested compiler for restic is the official Go compiler. Building restic with gccgo may work, but is not supported.
Usage help is available:
$ ./restic --help
Usage:
restic [OPTIONS] <command>
Application Options:
-r, --repo= Repository directory to backup to/restore from
Help Options:
-h, --help Show this help message
Available commands:
backup save file/directory
cache manage cache
cat dump something
find find a file/directory
fsck check the repository
init create repository
key manage keys
list lists data
ls list files
restore restore a snapshot
snapshots show snapshots
version display version
Similar to programs such as git, restic has a number of sub-commands. You can
see these commands in the listing above. Each sub-command may have own
command-line options, and there is a help option for each command which lists
them, e.g. for the backup command:
$ ./restic backup --help
Usage:
restic [OPTIONS] backup DIR/FILE [DIR/FILE] [...]
The backup command creates a snapshot of a file or directory
Application Options:
-r, --repo= Repository directory to backup to/restore from
--cache-dir= Directory to use as a local cache
-q, --quiet Do not output comprehensive progress report (false)
--no-lock Do not lock the repo, this allows some operations on read-only repos. (false)
Help Options:
-h, --help Show this help message
[backup command options]
-p, --parent= use this parent snapshot (default: last snapshot in repo that has the same target)
-f, --force Force re-reading the target. Overrides the "parent" flag
-e, --exclude= Exclude a pattern (can be specified multiple times)
Subcommand that support showing progress information such as backup, check and prune will do so unless
the quiet flag -q or --quiet is set. When running from a non-interactive console progress reporting will
be limited to once every 10 seconds to not fill your logs.
Additionally on Unix systems if restic receives a SIGUSR signal the current progress will written to the
standard output so you can check up on the status at will.
Initialize a repository
First, we need to create a "repository". This is the place where your backups will be saved at.
In order to create a repository at /tmp/backup, run the following command and
enter the same password twice:
$ restic init --repo /tmp/backup
enter password for new backend:
enter password again:
created restic backend 085b3c76b9 at /tmp/backup
Please note that knowledge of your password is required to access the repository.
Losing your password means that your data is irrecoverably lost.
Remembering your password is important! If you lose it, you won't be able to access data stored in the repository.
For automated backups, restic accepts the repository location in the
environment variable RESTIC_REPOSITORY and also the password in the variable
RESTIC_PASSWORD.
Password prompt on Windows
At the moment, restic only supports the default Windows console interaction.
If you use emulation environments like MSYS2 or
Cygwin, which use terminals like Mintty or rxvt,
you may get a password error:
You can workaround this by using a special tool called winpty (look
here and
here for detail information). On MSYS2,
you can install winpty as follows:
$ pacman -S winpty
$ winpty restic -r /tmp/backup init
Create a snapshot
Now we're ready to backup some data. The contents of a directory at a specific point in time is called a "snapshot" in restic. Run the following command and enter the repository password you chose above again:
$ restic -r /tmp/backup backup ~/work
enter password for repository:
scan [/home/user/work]
scanned 764 directories, 1816 files in 0:00
[0:29] 100.00% 54.732 MiB/s 1.582 GiB / 1.582 GiB 2580 / 2580 items 0 errors ETA 0:00
duration: 0:29, 54.47MiB/s
snapshot 40dc1520 saved
As you can see, restic created a backup of the directory and was pretty fast!
The specific snapshot just created is identified by a sequence of hexadecimal
characters, 40dc1520 in this case.
If you run the command again, restic will create another snapshot of your data, but this time it's even faster. This is de-duplication at work!
$ restic -r /tmp/backup backup ~/shared/work/web
enter password for repository:
using parent snapshot 40dc1520aa6a07b7b3ae561786770a01951245d2367241e71e9485f18ae8228c
scan [/home/user/work]
scanned 764 directories, 1816 files in 0:00
[0:00] 100.00% 0B/s 1.582 GiB / 1.582 GiB 2580 / 2580 items 0 errors ETA 0:00
duration: 0:00, 6572.38MiB/s
snapshot 79766175 saved
You can even backup individual files in the same repository.
$ restic -r /tmp/backup backup ~/work.txt
scan [~/work.txt]
scanned 0 directories, 1 files in 0:00
[0:00] 100.00% 0B/s 220B / 220B 1 / 1 items 0 errors ETA 0:00
duration: 0:00, 0.03MiB/s
snapshot 31f7bd63 saved
In fact several hosts may use the same repository to backup directories and files leading to a greater de-duplication.
You can exclude folders and files by specifying exclude-patterns.
Either specify them with multiple --exclude's or one --exclude-file
$ cat exclude
# exclude go-files
*.go
# exclude foo/x/y/z/bar foo/x/bar foo/bar
foo/**/bar
$ restic -r /tmp/backup backup ~/work --exclude=*.c --exclude-file=exclude
Patterns use filepath.Glob internally,
see filepath.Match for syntax.
Additionally ** exludes arbitrary subdirectories.
Environment-variables in exclude-files are expanded with os.ExpandEnv.
Reading data from stdin
Sometimes it can be nice to directly save the output of a program, e.g.
mysqldump so that the SQL can later be restored. Restic supports this mode of
operation, just supply the option --stdin to the backup command like this:
$ mysqldump [...] | restic -r /tmp/backup backup --stdin
This creates a new snapshot of the output of mysqldump. You can then use e.g.
the fuse mounting option (see below) to mount the repository and read the file.
By default, the file name stdin is used, a different name can be specified
with --stdin-filename, e.g. like this:
$ mysqldump [...] | restic -r /tmp/backup backup --stdin --stdin-filenam production.sql
List all snapshots
Now, you can list all the snapshots stored in the repository:
$ restic -r /tmp/backup snapshots
enter password for repository:
ID Date Host Directory
----------------------------------------------------------------------
40dc1520 2015-05-08 21:38:30 kasimir /home/user/work
79766175 2015-05-08 21:40:19 kasimir /home/user/work
bdbd3439 2015-05-08 21:45:17 luigi /home/art
590c8fc8 2015-05-08 21:47:38 kazik /srv
9f0bc19e 2015-05-08 21:46:11 luigi /srv
You can filter the listing by directory path:
$ restic -r /tmp/backup snapshots --path="/srv"
enter password for repository:
ID Date Host Directory
----------------------------------------------------------------------
590c8fc8 2015-05-08 21:47:38 kazik /srv
9f0bc19e 2015-05-08 21:46:11 luigi /srv
Or filter by host:
$ restic -r /tmp/backup snapshots --host luigi
enter password for repository:
ID Date Host Directory
----------------------------------------------------------------------
bdbd3439 2015-05-08 21:45:17 luigi /home/art
9f0bc19e 2015-05-08 21:46:11 luigi /srv
Combining filters is also possible.
Restore a snapshot
Restoring a snapshot is as easy as it sounds, just use the following command to
restore the contents of the latest snapshot to /tmp/restore-work:
$ restic -r /tmp/backup restore 79766175 --target ~/tmp/restore-work
enter password for repository:
restoring <Snapshot of [/home/user/work] at 2015-05-08 21:40:19.884408621 +0200 CEST> to /tmp/restore-work
Use the word latest to restore the last backup. You can also combine latest
with the --host and --path filters to choose the last backup for a specific
host, path or both.
$ restic -r /tmp/backup restore latest --target ~/tmp/restore-work --path "/home/art" --host luigi
enter password for repository:
restoring <Snapshot of [/home/art] at 2015-05-08 21:45:17.884408621 +0200 CEST> to /tmp/restore-work
Manage repository keys
The key command allows you to set multiple access keys or passwords per
repository. In fact, you can use the list, add, remove and passwd
sub-commands to manage these keys very precisely:
$ restic -r /tmp/backup key list
enter password for repository:
ID User Host Created
----------------------------------------------------------------------
*eb78040b username kasimir 2015-08-12 13:29:57
$ restic -r /tmp/backup key add
enter password for repository:
enter password for new key:
enter password again:
saved new key as <Key of username@kasimir, created on 2015-08-12 13:35:05.316831933 +0200 CEST>
$ restic -r backup key list
enter password for repository:
ID User Host Created
----------------------------------------------------------------------
5c657874 username kasimir 2015-08-12 13:35:05
*eb78040b username kasimir 2015-08-12 13:29:57
Check integrity and consistency
Imagine your repository is saved on a server that has a faulty hard drive, or even worse, attackers get privileged access and modify your backup with the intention to make you restore malicious data:
$ sudo echo "boom" >> backup/index/d795ffa99a8ab8f8e42cec1f814df4e48b8f49129360fb57613df93739faee97
In order to detect these things, it is a good idea to regularly use the check
command to test whether everything is alright, your precious backup data is
consistent and the integrity is unharmed:
$ restic -r /tmp/backup check
Load indexes
ciphertext verification failed
Trying to restore a snapshot which has been modified as shown above will yield the same error:
$ restic -r /tmp/backup restore 79766175 --target ~/tmp/restore-work
Load indexes
ciphertext verification failed
Mount a repository
Browsing your backup as a regular file system is also very easy. First, create
a mount point such as /mnt/restic and then use the following command to serve
the repository with FUSE:
$ mkdir /mnt/restic
$ restic -r /tmp/backup mount /mnt/restic
enter password for repository:
Now serving /tmp/backup at /tmp/restic
Don't forget to umount after quitting!
Windows doesn't support FUSE directly. Projects like dokan try to fill the gap. We haven't tested it yet, but we'd like to hear about your experience. For setup information see dokan FUSE in dokan's wiki.
Create an SFTP repository
In order to backup data via SFTP, you must first set up a server with SSH and let it know your public key. Passwordless login is really important since restic fails to connect to the repository if the server prompts for credentials.
Once the server is configured, the setup of the SFTP repository can simply be
achieved by changing the URL scheme in the init command:
$ restic -r sftp:user@host:/tmp/backup init
enter password for new backend:
enter password again:
created restic backend f1c6108821 at sftp:user@host:/tmp/backup
Please note that knowledge of your password is required to access the repository.
Losing your password means that your data is irrecoverably lost.
You can also specify a relative (read: no slash (/) character at the
beginning) directory, in this case the dir is relative to the remote user's
home directory.
Create an Amazon S3 repository
Restic can backup data to any Amazon S3 bucket. However, in this case, changing the URL scheme is not enough since Amazon uses special security credentials to sign HTTP requests. By consequence, you must first setup the following environment variables with the credentials you obtained while creating the bucket.
$ export AWS_ACCESS_KEY_ID=<MY_ACCESS_KEY>
$ export AWS_SECRET_ACCESS_KEY=<MY_SECRET_ACCESS_KEY>
You can then easily initialize a repository that uses your Amazon S3 as a backend.
$ restic -r s3:eu-central-1/bucket_name init
enter password for new backend:
enter password again:
created restic backend eefee03bbd at s3:eu-central-1/bucket_name
Please note that knowledge of your password is required to access the repository.
Losing your password means that your data is irrecoverably lost.
Fro an s3-compatible server that is not Amazon (like Minio, see below), or is
only available via HTTP, you can specify the URL to the server like this:
s3:http://server:port/bucket_name.
Create a Minio Server repository
Minio is an Open Source Object Storage, written in Go and compatible with AWS S3 API.
Pre-Requisites
- Download and Install Minio Server.
- You can also refer to https://docs.minio.io for step by step guidance on installation and getting started on Minio CLient and Minio Server.
You must first setup the following environment variables with the credentials of your running Minio Server.
$ export AWS_ACCESS_KEY_ID=<YOUR-MINIO-ACCESS-KEY-ID>
$ export AWS_SECRET_ACCESS_KEY= <YOUR-MINIO-SECRET-ACCESS-KEY>
Now you can easily initialize restic to use Minio server as backend with this command.
$ ./restic -r s3:http://localhost:9000/restic init
enter password for new backend:
enter password again:
created restic backend 6ad29560f5 at s3:http://localhost:9000/restic1
Please note that knowledge of your password is required to access
the repository. Losing your password means that your data is irrecoverably lost.
Removing old snapshots
All backup space is finite, so restic allows removing old snapshots. This can
be done either manually (by specifying a snapshot ID to remove) or by using a
policy that describes which snapshots to forget. For all remove operations, two
commands need to be called in sequence: forget to remove a snapshot and
prune to actually remove the data that was referenced by the snapshot from
the repository.
Remove a single snapshot
The command snapshots can be used to list all snapshots in a repository like this:
$ restic -r /tmp/backup snapshots
enter password for repository:
ID Date Host Directory
----------------------------------------------------------------------
40dc1520 2015-05-08 21:38:30 kasimir /home/user/work
79766175 2015-05-08 21:40:19 kasimir /home/user/work
bdbd3439 2015-05-08 21:45:17 luigi /home/art
590c8fc8 2015-05-08 21:47:38 kazik /srv
9f0bc19e 2015-05-08 21:46:11 luigi /srv
In order to remove the snapshot of /home/art, use the forget command and
specify the snapshot ID on the command line:
$ restic -r /tmp/backup forget bdbd3439
enter password for repository:
removed snapshot d3f01f63
Afterwards this snapshot is removed:
$ restic -r /tmp/backup snapshots
enter password for repository:
ID Date Host Directory
----------------------------------------------------------------------
40dc1520 2015-05-08 21:38:30 kasimir /home/user/work
79766175 2015-05-08 21:40:19 kasimir /home/user/work
590c8fc8 2015-05-08 21:47:38 kazik /srv
9f0bc19e 2015-05-08 21:46:11 luigi /srv
But the data that was referenced by files in this snapshot is still stored in
the repository. To cleanup unreferenced data, the prune command must be run:
$ restic -r /tmp/backup prune
enter password for repository:
counting files in repo
building new index for repo
[0:00] 100.00% 22 / 22 files
repository contains 22 packs (8512 blobs) with 100.092 MiB bytes
processed 8512 blobs: 0 duplicate blobs, 0B duplicate
load all snapshots
find data that is still in use for 1 snapshots
[0:00] 100.00% 1 / 1 snapshots
found 8433 of 8512 data blobs still in use
will rewrite 3 packs
creating new index
[0:00] 86.36% 19 / 22 files
saved new index as 544a5084
done
Afterwards the repository is smaller.
Removing snapshots according to a policy
Removing snapshots manually is tedious and error-prone, therefore restic allows
specifying which snapshots should be removed automatically according to a
policy. You can specify how many hourly, daily, weekly, monthly and yearly
snapshots to keep, any other snapshots are removed. The most important
command-line parameter here is --dry-run which instructs restic to not remove
anything but print which snapshots would be removed.
When forget is run with a policy, restic loads the list of all snapshots,
then groups these by host name and list of directories. The policy is then
applied to each group of snapshots separately. This is a safety feature.
The forget command accepts the following parameters:
--keep-last nnever delete thenlast (most recent) snapshots--keep-hourly nfor the lastnhours in which a snapshot was made, keep only the last snapshot for each hour.--keep-daily nfor the lastndays which have one or more snapshots, only keep the last one for that day.--keep-weekly nfor the lastnweeks which have one or more snapshots, only keep the last one for that week.--keep-monthly nfor the lastnmonths which have one or more snapshots, only keep the last one for that month.--keep-yearly nfor the lastnyears which have one or more snapshots, only keep the last one for that year.
Additionally, you can restrict removing snapshots to those which have a
particular hostname with the --hostname parameter.
All the --keep-* options above only count hours/days/weeks/months/years which
have a snapshot, so those without a snapshot are ignored.
Let's explain this with an example: Suppose you have only made a backup on each
Sunday for 12 weeks. Then forget --keep-daily 4 will keep the last four snapshots
for the last four Sundays, but remove the rest. Only counting the days which
have a backup and ignore the ones without is a safety feature: it prevents
restic from removing many snapshots when no new ones are created. If it was
implemented otherwise, running forget --keep-daily 4 on a Friday would remove
all snapshots!
Debugging restic
The program can be built with debug support like this:
$ go run build.go -tags debug
Afterwards, extensive debug messages are written to the file in environment
variable DEBUG_LOG, e.g.:
$ DEBUG_LOG=/tmp/restic-debug.log restic backup ~/work
If you suspect that there is a bug, you can have a look at the debug log. Please be aware that the debug log might contain sensitive information such as file and directory names.
Under the hood: Browse repository objects
Internally, a repository stores data of several different types described in the design documentation. You can list objects such as blobs, packs, index, snapshots, keys or locks with the following command:
$ restic -r /tmp/backup list snapshots
d369ccc7d126594950bf74f0a348d5d98d9e99f3215082eb69bf02dc9b3e464c
The find command searches for a given
pattern in the repository.
$ restic -r backup find test.txt
debug log file restic.log
debug enabled
enter password for repository:
found 1 matching entries in snapshot 196bc5760c909a7681647949e80e5448e276521489558525680acf1bd428af36
-rw-r--r-- 501 20 5 2015-08-26 14:09:57 +0200 CEST path/to/test.txt
The cat command allows you to display the JSON representation of the objects
or its raw content.
$ restic -r /tmp/backup cat snapshot d369ccc7d126594950bf74f0a348d5d98d9e99f3215082eb69bf02dc9b3e464c
enter password for repository:
{
"time": "2015-08-12T12:52:44.091448856+02:00",
"tree": "05cec17e8d3349f402576d02576a2971fc0d9f9776ce2f441c7010849c4ff5af",
"paths": [
"/home/user/work"
],
"hostname": "kasimir",
"username": "username",
"uid": 501,
"gid": 20
}