BORG-PATTERNS(1) | borg backup tool | BORG-PATTERNS(1) |
borg-patterns - Details regarding patterns
The path/filenames used as input for the pattern matching start from the currently active recursion root. You usually give the recursion root(s) when invoking borg and these can be either relative or absolute paths.
So, when you give relative/ as root, the paths going into the matcher will look like relative/.../file.ext. When you give /absolute/ as root, they will look like /absolute/.../file.ext. This is meant when we talk about "full path" below.
File paths in Borg archives are always stored normalized and relative. This means that e.g. borg create /path/to/repo ../some/path will store all files as some/path/.../file.ext and borg create /path/to/repo /home/user will store all files as home/user/.../file.ext. Therefore, always use relative paths in your patterns when matching archive content in commands like extract or mount. Starting with Borg 1.2 this behaviour will be changed to accept both absolute and relative paths.
File patterns support these styles: fnmatch, shell, regular expressions, path prefixes and path full-matches. By default, fnmatch is used for --exclude patterns and shell-style is used for the experimental --pattern option.
If followed by a colon (':') the first two characters of a pattern are used as a style selector. Explicit style selection is necessary when a non-default style is desired or when the desired pattern starts with two alphanumeric characters followed by a colon (i.e. aa:something/*).
Implementation note: this is implemented via very time-efficient O(1) hashtable lookups (this means you can have huge amounts of such patterns without impacting performance much). Due to that, this kind of pattern does not respect any context or order. If you use such a pattern to include a file, it will always be included (if the directory recursion encounters it). Other include/exclude patterns that would normally match will be ignored. Same logic applies for exclude.
NOTE:
Exclusions can be passed via the command line option --exclude. When used from within a shell, the patterns should be quoted to protect them from expansion.
The --exclude-from option permits loading exclusion patterns from a text file with one pattern per line. Lines empty or starting with the number sign ('#') after removing whitespace on both ends are ignored. The optional style selector prefix is also supported for patterns loaded from a file. Due to whitespace removal, paths with whitespace at the beginning or end can only be excluded using regular expressions.
To test your exclusion patterns without performing an actual backup you can run borg create --list --dry-run ....
Examples:
# Exclude '/home/user/file.o' but not '/home/user/file.odt': $ borg create -e '*.o' backup / # Exclude '/home/user/junk' and '/home/user/subdir/junk' but # not '/home/user/importantjunk' or '/etc/junk': $ borg create -e '/home/*/junk' backup / # Exclude the contents of '/home/user/cache' but not the directory itself: $ borg create -e /home/user/cache/ backup / # The file '/home/user/cache/important' is *not* backed up: $ borg create -e /home/user/cache/ backup / /home/user/cache/important # The contents of directories in '/home' are not backed up when their name # ends in '.tmp' $ borg create --exclude 're:^/home/[^/]+\.tmp/' backup / # Load exclusions from file $ cat >exclude.txt <<EOF # Comment line /home/*/junk *.tmp fm:aa:something/* re:^home/[^/]\.tmp/ sh:home/*/.thumbnails
# Example with spaces, no need to escape as it is processed by borg some file with spaces.txt EOF $ borg create --exclude-from exclude.txt backup /
NOTE:
Inclusion patterns are useful to include paths that are contained in an excluded path. The first matching pattern is used so if an include pattern matches before an exclude pattern, the file is backed up. If an exclude-norecurse pattern matches a directory, it won't recurse into it and won't discover any potential matches for include rules below that directory.
Note that the default pattern style for --pattern and --patterns-from is shell style (sh:), so those patterns behave similar to rsync include/exclude patterns. The pattern style can be set via the P prefix.
Patterns (--pattern) and excludes (--exclude) from the command line are considered first (in the order of appearance). Then patterns from --patterns-from are added. Exclusion patterns from --exclude-from files are appended last.
Examples:
# backup pics, but not the ones from 2018, except the good ones: # note: using = is essential to avoid cmdline argument parsing issues. borg create --pattern=+pics/2018/good --pattern=-pics/2018 repo::arch pics # use a file with patterns: borg create --patterns-from patterns.lst repo::arch
The patterns.lst file could look like that:
# "sh:" pattern style is the default, so the following line is not needed: P sh R / # can be rebuild - /home/*/.cache # they're downloads for a reason - /home/*/Downloads # susan is a nice person # include susans home + /home/susan # don't backup the other home directories - /home/* # don't even look in /proc ! /proc
The Borg Collective
2021-03-22 |