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 /srv/restic-repo --verbose backup ~/work open repository enter password for repository: password is correct lock repository load index files start scan start backup scan finished in 1.837s processed 1.720 GiB in 0:12 Files: 5307 new, 0 changed, 0 unmodified Dirs: 1867 new, 0 changed, 0 unmodified Added: 1.700 GiB 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
40dc1520 in this case.
If you don’t pass the
--verbose option, restic will print less data. You’ll still get a nice live status display. Be aware that the live status shows the processed files and not the transferred data. Transferred volume might be lower (due to deduplication) or higher.
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 /srv/restic-repo backup --verbose ~/work open repository enter password for repository: password is correct lock repository load index files using parent snapshot d875ae93 start scan start backup scan finished in 1.881s processed 1.720 GiB in 0:03 Files: 0 new, 0 changed, 5307 unmodified Dirs: 0 new, 0 changed, 1867 unmodified Added: 0 B snapshot 79766175 saved
You can even backup individual files in the same repository (not passing
--verbose means less output):
$ restic -r /srv/restic-repo backup ~/work.txt enter password for repository: password is correct snapshot 249d0210 saved
If you’re interested in what restic does, pass
--verbose twice (or
--verbose 2) to display detailed information about each file and directory
$ echo 'more data foo bar' >> ~/work.txt $ restic -r /srv/restic-repo backup --verbose --verbose ~/work.txt open repository enter password for repository: password is correct lock repository load index files using parent snapshot f3f8d56b start scan start backup scan finished in 2.115s modified /home/user/work.txt, saved in 0.007s (22 B added) modified /home/user/, saved in 0.008s (0 B added, 378 B metadata) modified /home/, saved in 0.009s (0 B added, 375 B metadata) processed 22 B in 0:02 Files: 0 new, 1 changed, 0 unmodified Dirs: 0 new, 2 changed, 0 unmodified Data Blobs: 1 new Tree Blobs: 3 new Added: 1.116 KiB snapshot 8dc503fc saved
In fact several hosts may use the same repository to backup directories and files leading to a greater de-duplication.
Please be aware that when you backup different directories (or the directories to be saved have a variable name component like a time/date), restic always needs to read all files and only afterwards can compute which parts of the files need to be saved. When you backup the same directory again (maybe with new or changed files) restic will find the old snapshot in the repo and by default only reads those files that are new or have been modified since the last snapshot. This is decided based on the modify date of the file in the file system.
Now is a good time to run
restic check to verify that all data
is properly stored in the repository. You should run this command regularly
to make sure the internal structure of the repository is free of errors.
Including and Excluding Files¶
You can exclude folders and files by specifying exclude patterns, currently the exclude options are:
--excludeSpecified one or more times to exclude one or more items
--exclude-cachesSpecified once to exclude folders containing a special file
--exclude-fileSpecified one or more times to exclude items listed in a given file
--exclude-if-presentSpecified one or more times to exclude a folders content if it contains a given file (optionally having a given header)
Let’s say we have a file called
excludes.txtwith the following content:
# exclude go-files *.go # exclude foo/x/y/z/bar foo/x/bar foo/bar foo/**/bar
It can be used like this:
$ restic -r /srv/restic-repo backup ~/work --exclude="*.c" --exclude-file=excludes.txt
This instruct restic to exclude files matching the following criteria:
- All files matching
*.go(second line in
- All files and sub-directories named
barwhich reside somewhere below a directory called
foo(fourth line in
- All files matching
restic help backup for more specific information about each exclude option.
Patterns use filepath.Glob internally, see filepath.Match for syntax. Patterns are tested against the full path of a file/dir to be saved, even if restic is passed a relative path to save. Environment-variables in exclude-files are expanded with os.ExpandEnv.
Patterns need to match on complete path components. For example, the pattern
- does not match
/ is ignored, a leading
/ anchors the
pattern at the root directory. This means,
does not match
Regular wildcards cannot be used to match over the
/. For example:
/bin/bash but does not match
For this, the special wildcard
** can be used to match arbitrary
sub-directories: The pattern
By specifying the option
--one-file-system you can instruct restic
to only backup files from the file systems the initially specified files
or directories reside on. For example, calling restic like this won’t
/dev on a Linux system:
$ restic -r /srv/restic-repo backup --one-file-system /
By using the
--files-from option you can read the files you want to
backup from a file. This is especially useful if a lot of files have to
be backed up that are not in the same folder or are maybe pre-filtered
by other software.
For example maybe you want to backup files which have a name that matches a certain pattern:
$ find /tmp/somefiles | grep 'PATTERN' > /tmp/files_to_backup
You can then use restic to backup the filtered files:
$ restic -r /srv/restic-repo backup --files-from /tmp/files_to_backup
Incidentally you can also combine
--files-from with the normal files
$ restic -r /srv/restic-repo backup --files-from /tmp/files_to_backup /tmp/some_additional_file
Paths in the listing file can be absolute or relative.
Restic has a diff command which shows the difference between two snapshots and displays a small statistic, just pass the command two snapshot IDs:
$ restic -r /srv/restic-repo diff 5845b002 2ab627a6 password is correct comparing snapshot ea657ce5 to 2ab627a6: C /restic/cmd_diff.go + /restic/foo C /restic/restic Files: 0 new, 0 removed, 2 changed Dirs: 1 new, 0 removed Others: 0 new, 0 removed Data Blobs: 14 new, 15 removed Tree Blobs: 2 new, 1 removed Added: 16.403 MiB Removed: 16.402 MiB
Backing up special items and metadata¶
Symlinks are archived as symlinks,
restic does not follow them.
When you restore, you get the same symlink again, with the same link target
and the same timestamps.
If there is a bind-mount below a directory that is to be saved, restic descends into it.
Device files are saved and restored as device files. This means that e.g.
archived as a block device file and restored as such. This also means that the content of the
corresponding disk is not read, at least not from the device file.
By default, restic does not save the access time (atime) for any files or other
items, since it is not possible to reliably disable updating the access time by
restic itself. This means that for each new backup a lot of metadata is
written, and the next backup needs to write new metadata again. If you really
want to save the access time for files and directories, you can pass the
--with-atime option to the
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 /srv/restic-repo 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
--stdin-filename, e.g. like this:
$ mysqldump [...] | restic -r /srv/restic-repo backup --stdin --stdin-filename production.sql
Restic currently assumes that your backup repository has sufficient space for the backup operation you are about to perform. This is a realistic assumption for many cloud providers, but may not be true when backing up to local disks.
Should you run out of space during the middle of a backup, there will be some additional data in the repository, but the snapshot will never be created as it would only be written at the very (successful) end of the backup operation. Previous snapshots will still be there and will still work.