.. include:: global.rst.inc .. highlight:: none .. _detailed_usage: Usage ===== |project_name| consists of a number of commands. Each command accepts a number of arguments and options. The following sections will describe each command in detail. General ------- Repository URLs ~~~~~~~~~~~~~~~ **Local filesystem** (or locally mounted network filesystem): ``/path/to/repo`` - filesystem path to repo directory, absolute path ``path/to/repo`` - filesystem path to repo directory, relative path Also, stuff like ``~/path/to/repo`` or ``~other/path/to/repo`` works (this is expanded by your shell). Note: you may also prepend a ``file://`` to a filesystem path to get URL style. **Remote repositories** accessed via ssh user@host: ``user@host:/path/to/repo`` - remote repo, absolute path ``ssh://user@host:port/path/to/repo`` - same, alternative syntax, port can be given **Remote repositories with relative pathes** can be given using this syntax: ``user@host:path/to/repo`` - path relative to current directory ``user@host:~/path/to/repo`` - path relative to user's home directory ``user@host:~other/path/to/repo`` - path relative to other's home directory Note: giving ``user@host:/./path/to/repo`` or ``user@host:/~/path/to/repo`` or ``user@host:/~other/path/to/repo`` is also supported, but not required here. **Remote repositories with relative pathes, alternative syntax with port**: ``ssh://user@host:port/./path/to/repo`` - path relative to current directory ``ssh://user@host:port/~/path/to/repo`` - path relative to user's home directory ``ssh://user@host:port/~other/path/to/repo`` - path relative to other's home directory If you frequently need the same repo URL, it is a good idea to set the ``BORG_REPO`` environment variable to set a default for the repo URL: :: export BORG_REPO='ssh://user@host:port/path/to/repo' Then just leave away the repo URL if only a repo URL is needed and you want to use the default - it will be read from BORG_REPO then. Use ``::`` syntax to give the repo URL when syntax requires giving a positional argument for the repo (e.g. ``borg mount :: /mnt``). Repository / Archive Locations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Many commands want either a repository (just give the repo URL, see above) or an archive location, which is a repo URL followed by ``::archive_name``. Archive names must not contain the ``/`` (slash) character. For simplicity, maybe also avoid blanks or other characters that have special meaning on the shell or in a filesystem (borg mount will use the archive name as directory name). If you have set BORG_REPO (see above) and an archive location is needed, use ``::archive_name`` - the repo URL part is then read from BORG_REPO. Type of log output ~~~~~~~~~~~~~~~~~~ The log level of the builtin logging configuration defaults to WARNING. This is because we want |project_name| to be mostly silent and only output warnings, errors and critical messages, unless output has been requested by supplying an option that implies output (eg, --list or --progress). Log levels: DEBUG < INFO < WARNING < ERROR < CRITICAL Use ``--debug`` to set DEBUG log level - to get debug, info, warning, error and critical level output. Use ``--info`` (or ``-v`` or ``--verbose``) to set INFO log level - to get info, warning, error and critical level output. Use ``--warning`` (default) to set WARNING log level - to get warning, error and critical level output. Use ``--error`` to set ERROR log level - to get error and critical level output. Use ``--critical`` to set CRITICAL log level - to get critical level output. While you can set misc. log levels, do not expect that every command will give different output on different log levels - it's just a possibility. .. warning:: Options --critical and --error are provided for completeness, their usage is not recommended as you might miss important information. Return codes ~~~~~~~~~~~~ |project_name| can exit with the following return codes (rc): :: 0 = success (logged as INFO) 1 = warning (operation reached its normal end, but there were warnings - you should check the log, logged as WARNING) 2 = error (like a fatal error, a local or remote exception, the operation did not reach its normal end, logged as ERROR) 128+N = killed by signal N (e.g. 137 == kill -9) If you use ``--show-rc``, the return code is also logged at the indicated level as the last log entry. Environment Variables ~~~~~~~~~~~~~~~~~~~~~ |project_name| uses some environment variables for automation: General: BORG_REPO When set, use the value to give the default repository location. If a command needs an archive parameter, you can abbreviate as `::archive`. If a command needs a repository parameter, you can either leave it away or abbreviate as `::`, if a positional parameter is required. BORG_PASSPHRASE When set, use the value to answer the passphrase question for encrypted repositories. It is used when a passphrase is needed to access a encrypted repo as well as when a new passphrase should be initially set when initializing an encrypted repo. See also BORG_NEW_PASSPHRASE. BORG_NEW_PASSPHRASE When set, use the value to answer the passphrase question when a **new** passphrase is asked for. This variable is checked first. If it is not set, BORG_PASSPHRASE will be checked also. Main usecase for this is to fully automate ``borg change-passphrase``. BORG_DISPLAY_PASSPHRASE When set, use the value to answer the "display the passphrase for verification" question when defining a new passphrase for encrypted repositories. BORG_LOGGING_CONF When set, use the given filename as INI_-style logging configuration. BORG_RSH When set, use this command instead of ``ssh``. This can be used to specify ssh options, such as a custom identity file ``ssh -i /path/to/private/key``. See ``man ssh`` for other options. BORG_REMOTE_PATH When set, use the given path/filename as remote path (default is "borg"). Using ``--remote-path PATH`` commandline option overrides the environment variable. BORG_FILES_CACHE_TTL When set to a numeric value, this determines the maximum "time to live" for the files cache entries (default: 20). The files cache is used to quickly determine whether a file is unchanged. The FAQ explains this more detailed in: :ref:`always_chunking` TMPDIR where temporary files are stored (might need a lot of temporary space for some operations) Some automatic "answerers" (if set, they automatically answer confirmation questions): BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK=no (or =yes) For "Warning: Attempting to access a previously unknown unencrypted repository" BORG_RELOCATED_REPO_ACCESS_IS_OK=no (or =yes) For "Warning: The repository at location ... was previously located at ..." BORG_CHECK_I_KNOW_WHAT_I_AM_DOING=NO (or =YES) For "Warning: 'check --repair' is an experimental feature that might result in data loss." BORG_DELETE_I_KNOW_WHAT_I_AM_DOING=NO (or =YES) For "You requested to completely DELETE the repository *including* all archives it contains:" BORG_RECREATE_I_KNOW_WHAT_I_AM_DOING=NO (or =YES) For "recreate is an experimental feature." Note: answers are case sensitive. setting an invalid answer value might either give the default answer or ask you interactively, depending on whether retries are allowed (they by default are allowed). So please test your scripts interactively before making them a non-interactive script. Directories and files: BORG_KEYS_DIR Default to '~/.config/borg/keys'. This directory contains keys for encrypted repositories. BORG_KEY_FILE When set, use the given filename as repository key file. BORG_SECURITY_DIR Default to '~/.config/borg/security'. This directory contains information borg uses to track its usage of NONCES ("numbers used once" - usually in encryption context) and other security relevant data. BORG_CACHE_DIR Default to '~/.cache/borg'. This directory contains the local cache and might need a lot of space for dealing with big repositories). Building: BORG_OPENSSL_PREFIX Adds given OpenSSL header file directory to the default locations (setup.py). BORG_LZ4_PREFIX Adds given LZ4 header file directory to the default locations (setup.py). BORG_LIBB2_PREFIX Adds given prefix directory to the default locations. If a 'include/blake2.h' is found Borg will be linked against the system libb2 instead of a bundled implementation. (setup.py) Please note: - be very careful when using the "yes" sayers, the warnings with prompt exist for your / your data's security/safety - also be very careful when putting your passphrase into a script, make sure it has appropriate file permissions (e.g. mode 600, root:root). .. _INI: https://docs.python.org/3.4/library/logging.config.html#configuration-file-format Resource Usage ~~~~~~~~~~~~~~ |project_name| might use a lot of resources depending on the size of the data set it is dealing with. If one uses |project_name| in a client/server way (with a ssh: repository), the resource usage occurs in part on the client and in another part on the server. If one uses |project_name| as a single process (with a filesystem repo), all the resource usage occurs in that one process, so just add up client + server to get the approximate resource usage. CPU client: borg create: does chunking, hashing, compression, crypto (high CPU usage) chunks cache sync: quite heavy on CPU, doing lots of hashtable operations. borg extract: crypto, decompression (medium to high CPU usage) borg check: similar to extract, but depends on options given. borg prune / borg delete archive: low to medium CPU usage borg delete repo: done on the server It won't go beyond 100% of 1 core as the code is currently single-threaded. Especially higher zlib and lzma compression levels use significant amounts of CPU cycles. Crypto might be cheap on the CPU (if hardware accelerated) or expensive (if not). CPU server: It usually doesn't need much CPU, it just deals with the key/value store (repository) and uses the repository index for that. borg check: the repository check computes the checksums of all chunks (medium CPU usage) borg delete repo: low CPU usage CPU (only for client/server operation): When using borg in a client/server way with a ssh:-type repo, the ssh processes used for the transport layer will need some CPU on the client and on the server due to the crypto they are doing - esp. if you are pumping big amounts of data. Memory (RAM) client: The chunks index and the files index are read into memory for performance reasons. Might need big amounts of memory (see below). Compression, esp. lzma compression with high levels might need substantial amounts of memory. Memory (RAM) server: The server process will load the repository index into memory. Might need considerable amounts of memory, but less than on the client (see below). Chunks index (client only): Proportional to the amount of data chunks in your repo. Lots of chunks in your repo imply a big chunks index. It is possible to tweak the chunker params (see create options). Files index (client only): Proportional to the amount of files in your last backups. Can be switched off (see create options), but next backup might be much slower if you do. The speed benefit of using the files cache is proportional to file size. Repository index (server only): Proportional to the amount of data chunks in your repo. Lots of chunks in your repo imply a big repository index. It is possible to tweak the chunker params (see create options) to influence the amount of chunks being created. Temporary files (client): Reading data and metadata from a FUSE mounted repository will consume up to the size of all deduplicated, small chunks in the repository. Big chunks won't be locally cached. Temporary files (server): None. Cache files (client only): Contains the chunks index and files index (plus a collection of single- archive chunk indexes which might need huge amounts of disk space, depending on archive count and size - see FAQ about how to reduce). Network (only for client/server operation): If your repository is remote, all deduplicated (and optionally compressed/ encrypted) data of course has to go over the connection (ssh: repo url). If you use a locally mounted network filesystem, additionally some copy operations used for transaction support also go over the connection. If you backup multiple sources to one target repository, additional traffic happens for cache resynchronization. In case you are interested in more details (like formulas), please see :ref:`internals`. File systems ~~~~~~~~~~~~ We strongly recommend against using Borg (or any other database-like software) on non-journaling file systems like FAT, since it is not possible to assume any consistency in case of power failures (or a sudden disconnect of an external drive or similar failures). While Borg uses a data store that is resilient against these failures when used on journaling file systems, it is not possible to guarantee this with some hardware -- independent of the software used. We don't know a list of affected hardware. If you are suspicious whether your Borg repository is still consistent and readable after one of the failures mentioned above occured, run ``borg check --verify-data`` to make sure it is consistent. Units ~~~~~ To display quantities, |project_name| takes care of respecting the usual conventions of scale. Disk sizes are displayed in `decimal `_, using powers of ten (so ``kB`` means 1000 bytes). For memory usage, `binary prefixes `_ are used, and are indicated using the `IEC binary prefixes `_, using powers of two (so ``KiB`` means 1024 bytes). Date and Time ~~~~~~~~~~~~~ We format date and time conforming to ISO-8601, that is: YYYY-MM-DD and HH:MM:SS (24h clock). For more information about that, see: https://xkcd.com/1179/ Unless otherwise noted, we display local date and time. Internally, we store and process date and time as UTC. Common options ~~~~~~~~~~~~~~ All |project_name| commands share these options: .. include:: usage/common-options.rst.inc .. include:: usage/init.rst.inc Examples ~~~~~~~~ :: # Local repository, repokey encryption, BLAKE2b (often faster, since Borg 1.1) $ borg init --encryption=repokey-blake2 /path/to/repo # Local repository (no encryption) $ borg init --encryption=none /path/to/repo # Remote repository (accesses a remote borg via ssh) $ borg init --encryption=repokey-blake2 user@hostname:backup # Remote repository (store the key your home dir) $ borg init --encryption=keyfile user@hostname:backup .. include:: usage/create.rst.inc Examples ~~~~~~~~ :: # Backup ~/Documents into an archive named "my-documents" $ borg create /path/to/repo::my-documents ~/Documents # same, but list all files as we process them $ borg create --list /path/to/repo::my-documents ~/Documents # Backup ~/Documents and ~/src but exclude pyc files $ borg create /path/to/repo::my-files \ ~/Documents \ ~/src \ --exclude '*.pyc' # Backup home directories excluding image thumbnails (i.e. only # /home/*/.thumbnails is excluded, not /home/*/*/.thumbnails) $ borg create /path/to/repo::my-files /home \ --exclude 're:^/home/[^/]+/\.thumbnails/' # Do the same using a shell-style pattern $ borg create /path/to/repo::my-files /home \ --exclude 'sh:/home/*/.thumbnails' # Backup the root filesystem into an archive named "root-YYYY-MM-DD" # use zlib compression (good, but slow) - default is no compression $ borg create -C zlib,6 /path/to/repo::root-{now:%Y-%m-%d} / --one-file-system # Backup a remote host locally ("pull" style) using sshfs $ mkdir sshfs-mount $ sshfs root@example.com:/ sshfs-mount $ cd sshfs-mount $ borg create /path/to/repo::example.com-root-{now:%Y-%m-%d} . $ cd .. $ fusermount -u sshfs-mount # Make a big effort in fine granular deduplication (big chunk management # overhead, needs a lot of RAM and disk space, see formula in internals # docs - same parameters as borg < 1.0 or attic): $ borg create --chunker-params 10,23,16,4095 /path/to/repo::small /smallstuff # Backup a raw device (must not be active/in use/mounted at that time) $ dd if=/dev/sdx bs=10M | borg create /path/to/repo::my-sdx - # No compression (default) $ borg create /path/to/repo::arch ~ # Super fast, low compression $ borg create --compression lz4 /path/to/repo::arch ~ # Less fast, higher compression (N = 0..9) $ borg create --compression zlib,N /path/to/repo::arch ~ # Even slower, even higher compression (N = 0..9) $ borg create --compression lzma,N /path/to/repo::arch ~ # Use short hostname, user name and current time in archive name $ borg create /path/to/repo::{hostname}-{user}-{now} ~ # Similar, use the same datetime format as borg 1.1 will have as default $ borg create /path/to/repo::{hostname}-{user}-{now:%Y-%m-%dT%H:%M:%S} ~ # As above, but add nanoseconds $ borg create /path/to/repo::{hostname}-{user}-{now:%Y-%m-%dT%H:%M:%S.%f} ~ Notes ~~~~~ - the --exclude patterns are not like tar. In tar --exclude .bundler/gems will exclude foo/.bundler/gems. In borg it will not, you need to use --exclude '\*/.bundler/gems' to get the same effect. See ``borg help patterns`` for more information. .. include:: usage/extract.rst.inc Examples ~~~~~~~~ :: # Extract entire archive $ borg extract /path/to/repo::my-files # Extract entire archive and list files while processing $ borg extract --list /path/to/repo::my-files # Verify whether an archive could be successfully extracted, but do not write files to disk $ borg extract --dry-run /path/to/repo::my-files # Extract the "src" directory $ borg extract /path/to/repo::my-files home/USERNAME/src # Extract the "src" directory but exclude object files $ borg extract /path/to/repo::my-files home/USERNAME/src --exclude '*.o' # Restore a raw device (must not be active/in use/mounted at that time) $ borg extract --stdout /path/to/repo::my-sdx | dd of=/dev/sdx bs=10M .. Note:: Currently, extract always writes into the current working directory ("."), so make sure you ``cd`` to the right place before calling ``borg extract``. .. include:: usage/check.rst.inc .. include:: usage/rename.rst.inc Examples ~~~~~~~~ :: $ borg create /path/to/repo::archivename ~ $ borg list /path/to/repo archivename Mon, 2016-02-15 19:50:19 $ borg rename /path/to/repo::archivename newname $ borg list /path/to/repo newname Mon, 2016-02-15 19:50:19 .. include:: usage/list.rst.inc Examples ~~~~~~~~ :: $ borg list /path/to/repo Monday Mon, 2016-02-15 19:15:11 repo Mon, 2016-02-15 19:26:54 root-2016-02-15 Mon, 2016-02-15 19:36:29 newname Mon, 2016-02-15 19:50:19 ... $ borg list /path/to/repo::root-2016-02-15 drwxr-xr-x root root 0 Mon, 2016-02-15 17:44:27 . drwxrwxr-x root root 0 Mon, 2016-02-15 19:04:49 bin -rwxr-xr-x root root 1029624 Thu, 2014-11-13 00:08:51 bin/bash lrwxrwxrwx root root 0 Fri, 2015-03-27 20:24:26 bin/bzcmp -> bzdiff -rwxr-xr-x root root 2140 Fri, 2015-03-27 20:24:22 bin/bzdiff ... $ borg list /path/to/repo::archiveA --list-format="{mode} {user:6} {group:6} {size:8d} {isomtime} {path}{extra}{NEWLINE}" drwxrwxr-x user user 0 Sun, 2015-02-01 11:00:00 . drwxrwxr-x user user 0 Sun, 2015-02-01 11:00:00 code drwxrwxr-x user user 0 Sun, 2015-02-01 11:00:00 code/myproject -rw-rw-r-- user user 1416192 Sun, 2015-02-01 11:00:00 code/myproject/file.ext ... .. include:: usage/diff.rst.inc Examples ~~~~~~~~ :: $ borg init -e=none testrepo $ mkdir testdir $ cd testdir $ echo asdf > file1 $ dd if=/dev/urandom bs=1M count=4 > file2 $ touch file3 $ borg create ../testrepo::archive1 . $ chmod a+x file1 $ echo "something" >> file2 $ borg create ../testrepo::archive2 . $ rm file3 $ touch file4 $ borg create ../testrepo::archive3 . $ cd .. $ borg diff testrepo::archive1 archive2 [-rw-r--r-- -> -rwxr-xr-x] file1 +135 B -252 B file2 $ borg diff testrepo::archive2 archive3 added 0 B file4 removed 0 B file3 $ borg diff testrepo::archive1 archive3 [-rw-r--r-- -> -rwxr-xr-x] file1 +135 B -252 B file2 added 0 B file4 removed 0 B file3 .. include:: usage/delete.rst.inc Examples ~~~~~~~~ :: # delete a single backup archive: $ borg delete /path/to/repo::Monday # delete the whole repository and the related local cache: $ borg delete /path/to/repo You requested to completely DELETE the repository *including* all archives it contains: repo Mon, 2016-02-15 19:26:54 root-2016-02-15 Mon, 2016-02-15 19:36:29 newname Mon, 2016-02-15 19:50:19 Type 'YES' if you understand this and want to continue: YES .. include:: usage/prune.rst.inc Examples ~~~~~~~~ Be careful, prune is a potentially dangerous command, it will remove backup archives. The default of prune is to apply to **all archives in the repository** unless you restrict its operation to a subset of the archives using ``--prefix``. When using ``--prefix``, be careful to choose a good prefix - e.g. do not use a prefix "foo" if you do not also want to match "foobar". It is strongly recommended to always run ``prune -v --list --dry-run ...`` first so you will see what it would do without it actually doing anything. There is also a visualized prune example in ``docs/misc/prune-example.txt``. :: # Keep 7 end of day and 4 additional end of week archives. # Do a dry-run without actually deleting anything. $ borg prune -v --list --dry-run --keep-daily=7 --keep-weekly=4 /path/to/repo # Same as above but only apply to archive names starting with the hostname # of the machine followed by a "-" character: $ borg prune -v --list --keep-daily=7 --keep-weekly=4 --prefix='{hostname}-' /path/to/repo # Keep 7 end of day, 4 additional end of week archives, # and an end of month archive for every month: $ borg prune -v --list --keep-daily=7 --keep-weekly=4 --keep-monthly=-1 /path/to/repo # Keep all backups in the last 10 days, 4 additional end of week archives, # and an end of month archive for every month: $ borg prune -v --list --keep-within=10d --keep-weekly=4 --keep-monthly=-1 /path/to/repo .. include:: usage/info.rst.inc Examples ~~~~~~~~ :: $ borg info /path/to/repo::root-2016-02-15 Name: root-2016-02-15 Fingerprint: 57c827621f21b000a8d363c1e163cc55983822b3afff3a96df595077a660be50 Hostname: myhostname Username: root Time (start): Mon, 2016-02-15 19:36:29 Time (end): Mon, 2016-02-15 19:39:26 Command line: /usr/local/bin/borg create --list -C zlib,6 /path/to/repo::root-2016-02-15 / --one-file-system Number of files: 38100 Original size Compressed size Deduplicated size This archive: 1.33 GB 613.25 MB 571.64 MB All archives: 1.63 GB 853.66 MB 584.12 MB Unique chunks Total chunks Chunk index: 36858 48844 .. include:: usage/mount.rst.inc .. include:: usage/umount.rst.inc Examples ~~~~~~~~ borg mount ++++++++++ :: $ borg mount /path/to/repo::root-2016-02-15 /tmp/mymountpoint $ ls /tmp/mymountpoint bin boot etc home lib lib64 lost+found media mnt opt root sbin srv tmp usr var $ borg umount /tmp/mymountpoint :: $ borg mount -o versions /path/to/repo /tmp/mymountpoint $ ls -l /tmp/mymountpoint/home/user/doc.txt/ total 24 -rw-rw-r-- 1 user group 12357 Aug 26 21:19 doc.txt.cda00bc9 -rw-rw-r-- 1 user group 12204 Aug 26 21:04 doc.txt.fa760f28 $ fusermount -u /tmp/mymountpoint borgfs ++++++ :: $ echo '/mnt/backup /tmp/myrepo fuse.borgfs defaults,noauto 0 0' >> /etc/fstab $ echo '/mnt/backup::root-2016-02-15 /tmp/myarchive fuse.borgfs defaults,noauto 0 0' >> /etc/fstab $ mount /tmp/myrepo $ mount /tmp/myarchive $ ls /tmp/myrepo root-2016-02-01 root-2016-02-2015 $ ls /tmp/myarchive bin boot etc home lib lib64 lost+found media mnt opt root sbin srv tmp usr var .. Note:: ``borgfs`` will be automatically provided if you used a distribution package, ``pip`` or ``setup.py`` to install |project_name|. Users of the standalone binary will have to manually create a symlink (see :ref:`pyinstaller-binary`). .. include:: usage/key_export.rst.inc .. include:: usage/key_import.rst.inc .. _borg-change-passphrase: .. include:: usage/key_change-passphrase.rst.inc Examples ~~~~~~~~ :: # Create a key file protected repository $ borg init --encryption=keyfile -v /path/to/repo Initializing repository at "/path/to/repo" Enter new passphrase: Enter same passphrase again: Remember your passphrase. Your data will be inaccessible without it. Key in "/root/.config/borg/keys/mnt_backup" created. Keep this key safe. Your data will be inaccessible without it. Synchronizing chunks cache... Archives: 0, w/ cached Idx: 0, w/ outdated Idx: 0, w/o cached Idx: 0. Done. # Change key file passphrase $ borg key change-passphrase -v /path/to/repo Enter passphrase for key /root/.config/borg/keys/mnt_backup: Enter new passphrase: Enter same passphrase again: Remember your passphrase. Your data will be inaccessible without it. Key updated Fully automated using environment variables: :: $ BORG_NEW_PASSPHRASE=old borg init -e=repokey repo # now "old" is the current passphrase. $ BORG_PASSPHRASE=old BORG_NEW_PASSPHRASE=new borg key change-passphrase repo # now "new" is the current passphrase. .. include:: usage/serve.rst.inc Examples ~~~~~~~~ borg serve has special support for ssh forced commands (see ``authorized_keys`` example below): it will detect that you use such a forced command and extract the value of the ``--restrict-to-path`` option(s). It will then parse the original command that came from the client, makes sure that it is also ``borg serve`` and enforce path restriction(s) as given by the forced command. That way, other options given by the client (like ``--info`` or ``--umask``) are preserved (and are not fixed by the forced command). :: # Allow an SSH keypair to only run borg, and only have access to /path/to/repo. # Use key options to disable unneeded and potentially dangerous SSH functionality. # This will help to secure an automated remote backup system. $ cat ~/.ssh/authorized_keys command="borg serve --restrict-to-path /path/to/repo",no-pty,no-agent-forwarding,no-port-forwarding,no-X11-forwarding,no-user-rc ssh-rsa AAAAB3[...] .. include:: usage/upgrade.rst.inc Examples ~~~~~~~~ :: # Upgrade the borg repository to the most recent version. $ borg upgrade -v /path/to/repo making a hardlink copy in /path/to/repo.upgrade-2016-02-15-20:51:55 opening attic repository with borg and converting no key file found for repository converting repo index /path/to/repo/index.0 converting 1 segments... converting borg 0.xx to borg current no key file found for repository Upgrading a passphrase encrypted attic repo ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ attic offered a "passphrase" encryption mode, but this was removed in borg 1.0 and replaced by the "repokey" mode (which stores the passphrase-protected encryption key into the repository config). Thus, to upgrade a "passphrase" attic repo to a "repokey" borg repo, 2 steps are needed, in this order: - borg upgrade repo - borg key migrate-to-repokey repo .. include:: usage/recreate.rst.inc Examples ~~~~~~~~ :: # Make old (Attic / Borg 0.xx) archives deduplicate with Borg 1.x archives # Archives created with Borg 1.1+ and the default chunker params are skipped (archive ID stays the same) $ borg recreate /mnt/backup --chunker-params default --progress # Create a backup with little but fast compression $ borg create /mnt/backup::archive /some/files --compression lz4 # Then compress it - this might take longer, but the backup has already completed, so no inconsistencies # from a long-running backup job. $ borg recreate /mnt/backup::archive --compression zlib,9 # Remove unwanted files from all archives in a repository $ borg recreate /mnt/backup -e /home/icke/Pictures/drunk_photos # Change archive comment $ borg create --comment "This is a comment" /mnt/backup::archivename ~ $ borg info /mnt/backup::archivename Name: archivename Fingerprint: ... Comment: This is a comment ... $ borg recreate --comment "This is a better comment" /mnt/backup::archivename $ borg info /mnt/backup::archivename Name: archivename Fingerprint: ... Comment: This is a better comment ... .. include:: usage/with-lock.rst.inc .. include:: usage/break-lock.rst.inc Miscellaneous Help ------------------ .. include:: usage/help.rst.inc Debug Commands -------------- There is a ``borg debug`` command that has some subcommands which are all **not intended for normal use** and **potentially very dangerous** if used incorrectly. For example, ``borg debug put-obj`` and ``borg debug delete-obj`` will only do what their name suggests: put objects into repo / delete objects from repo. Please note: - they will not update the chunks cache (chunks index) about the object - they will not update the manifest (so no automatic chunks index resync is triggered) - they will not check whether the object is in use (e.g. before delete-obj) - they will not update any metadata which may point to the object They exist to improve debugging capabilities without direct system access, e.g. in case you ever run into some severe malfunction. Use them only if you know what you are doing or if a trusted |project_name| developer tells you what to do. Additional Notes ---------------- Here are misc. notes about topics that are maybe not covered in enough detail in the usage section. Item flags ~~~~~~~~~~ ``borg create --list`` outputs a list of all files, directories and other file system items it considered (no matter whether they had content changes or not). For each item, it prefixes a single-letter flag that indicates type and/or status of the item. If you are interested only in a subset of that output, you can give e.g. ``--filter=AME`` and it will only show regular files with A, M or E status (see below). A uppercase character represents the status of a regular file relative to the "files" cache (not relative to the repo -- this is an issue if the files cache is not used). Metadata is stored in any case and for 'A' and 'M' also new data chunks are stored. For 'U' all data chunks refer to already existing chunks. - 'A' = regular file, added (see also :ref:`a_status_oddity` in the FAQ) - 'M' = regular file, modified - 'U' = regular file, unchanged - 'E' = regular file, an error happened while accessing/reading *this* file A lowercase character means a file type other than a regular file, borg usually just stores their metadata: - 'd' = directory - 'b' = block device - 'c' = char device - 'h' = regular file, hardlink (to already seen inodes) - 's' = symlink - 'f' = fifo Other flags used include: - 'i' = backup data was read from standard input (stdin) - '-' = dry run, item was *not* backed up - 'x' = excluded, item was *not* backed up - '?' = missing status code (if you see this, please file a bug report!) --chunker-params ~~~~~~~~~~~~~~~~ The chunker params influence how input files are cut into pieces (chunks) which are then considered for deduplication. They also have a big impact on resource usage (RAM and disk space) as the amount of resources needed is (also) determined by the total amount of chunks in the repository (see `Indexes / Caches memory usage` for details). ``--chunker-params=10,23,16,4095`` results in a fine-grained deduplication and creates a big amount of chunks and thus uses a lot of resources to manage them. This is good for relatively small data volumes and if the machine has a good amount of free RAM and disk space. ``--chunker-params=19,23,21,4095`` (default) results in a coarse-grained deduplication and creates a much smaller amount of chunks and thus uses less resources. This is good for relatively big data volumes and if the machine has a relatively low amount of free RAM and disk space. If you already have made some archives in a repository and you then change chunker params, this of course impacts deduplication as the chunks will be cut differently. In the worst case (all files are big and were touched in between backups), this will store all content into the repository again. Usually, it is not that bad though: - usually most files are not touched, so it will just re-use the old chunks it already has in the repo - files smaller than the (both old and new) minimum chunksize result in only one chunk anyway, so the resulting chunks are same and deduplication will apply If you switch chunker params to save resources for an existing repo that already has some backup archives, you will see an increasing effect over time, when more and more files have been touched and stored again using the bigger chunksize **and** all references to the smaller older chunks have been removed (by deleting / pruning archives). If you want to see an immediate big effect on resource usage, you better start a new repository when changing chunker params. For more details, see :ref:`chunker_details`. --umask ~~~~~~~ If you use ``--umask``, make sure that all repository-modifying borg commands (create, delete, prune) that access the repository in question use the same ``--umask`` value. If multiple machines access the same repository, this should hold true for all of them. --read-special ~~~~~~~~~~~~~~ The --read-special option is special - you do not want to use it for normal full-filesystem backups, but rather after carefully picking some targets for it. The option ``--read-special`` triggers special treatment for block and char device files as well as FIFOs. Instead of storing them as such a device (or FIFO), they will get opened, their content will be read and in the backup archive they will show up like a regular file. Symlinks will also get special treatment if (and only if) they point to such a special file: instead of storing them as a symlink, the target special file will get processed as described above. One intended use case of this is backing up the contents of one or multiple block devices, like e.g. LVM snapshots or inactive LVs or disk partitions. You need to be careful about what you include when using ``--read-special``, e.g. if you include ``/dev/zero``, your backup will never terminate. Restoring such files' content is currently only supported one at a time via ``--stdout`` option (and you have to redirect stdout to where ever it shall go, maybe directly into an existing device file of your choice or indirectly via ``dd``). To some extent, mounting a backup archive with the backups of special files via ``borg mount`` and then loop-mounting the image files from inside the mount point will work. If you plan to access a lot of data in there, it likely will scale and perform better if you do not work via the FUSE mount. Example +++++++ Imagine you have made some snapshots of logical volumes (LVs) you want to backup. .. note:: For some scenarios, this is a good method to get "crash-like" consistency (I call it crash-like because it is the same as you would get if you just hit the reset button or your machine would abrubtly and completely crash). This is better than no consistency at all and a good method for some use cases, but likely not good enough if you have databases running. Then you create a backup archive of all these snapshots. The backup process will see a "frozen" state of the logical volumes, while the processes working in the original volumes continue changing the data stored there. You also add the output of ``lvdisplay`` to your backup, so you can see the LV sizes in case you ever need to recreate and restore them. After the backup has completed, you remove the snapshots again. :: $ # create snapshots here $ lvdisplay > lvdisplay.txt $ borg create --read-special /path/to/repo::arch lvdisplay.txt /dev/vg0/*-snapshot $ # remove snapshots here Now, let's see how to restore some LVs from such a backup. :: $ borg extract /path/to/repo::arch lvdisplay.txt $ # create empty LVs with correct sizes here (look into lvdisplay.txt). $ # we assume that you created an empty root and home LV and overwrite it now: $ borg extract --stdout /path/to/repo::arch dev/vg0/root-snapshot > /dev/vg0/root $ borg extract --stdout /path/to/repo::arch dev/vg0/home-snapshot > /dev/vg0/home .. _append_only_mode: Append-only mode ~~~~~~~~~~~~~~~~ A repository can be made "append-only", which means that Borg will never overwrite or delete committed data (append-only refers to the segment files, but borg will also reject to delete the repository completely). This is useful for scenarios where a backup client machine backups remotely to a backup server using ``borg serve``, since a hacked client machine cannot delete backups on the server permanently. To activate append-only mode, edit the repository ``config`` file and add a line ``append_only=1`` to the ``[repository]`` section (or edit the line if it exists). In append-only mode Borg will create a transaction log in the ``transactions`` file, where each line is a transaction and a UTC timestamp. In addition, ``borg serve`` can act as if a repository is in append-only mode with its option ``--append-only``. This can be very useful for fine-tuning access control in ``.ssh/authorized_keys`` :: command="borg serve --append-only ..." ssh-rsa command="borg serve ..." ssh-rsa Example +++++++ Suppose an attacker remotely deleted all backups, but your repository was in append-only mode. A transaction log in this situation might look like this: :: transaction 1, UTC time 2016-03-31T15:53:27.383532 transaction 5, UTC time 2016-03-31T15:53:52.588922 transaction 11, UTC time 2016-03-31T15:54:23.887256 transaction 12, UTC time 2016-03-31T15:55:54.022540 transaction 13, UTC time 2016-03-31T15:55:55.472564 From your security logs you conclude the attacker gained access at 15:54:00 and all the backups where deleted or replaced by compromised backups. From the log you know that transactions 11 and later are compromised. Note that the transaction ID is the name of the *last* file in the transaction. For example, transaction 11 spans files 6 to 11. In a real attack you'll likely want to keep the compromised repository intact to analyze what the attacker tried to achieve. It's also a good idea to make this copy just in case something goes wrong during the recovery. Since recovery is done by deleting some files, a hard link copy (``cp -al``) is sufficient. The first step to reset the repository to transaction 5, the last uncompromised transaction, is to remove the ``hints.N`` and ``index.N`` files in the repository (these two files are always expendable). In this example N is 13. Then remove or move all segment files from the segment directories in ``data/`` starting with file 6:: rm data/**/{6..13} That's all to it. Drawbacks +++++++++ As data is only appended, and nothing removed, commands like ``prune`` or ``delete`` won't free disk space, they merely tag data as deleted in a new transaction. Be aware that as soon as you write to the repo in non-append-only mode (e.g. prune, delete or create archives from an admin machine), it will remove the deleted objects permanently (including the ones that were already marked as deleted, but not removed, in append-only mode). Note that you can go back-and-forth between normal and append-only operation by editing the configuration file, it's not a "one way trip". Further considerations ++++++++++++++++++++++ Append-only mode is not respected by tools other than Borg. ``rm`` still works on the repository. Make sure that backup client machines only get to access the repository via ``borg serve``. Ensure that no remote access is possible if the repository is temporarily set to normal mode for e.g. regular pruning. Further protections can be implemented, but are outside of Borg's scope. For example, file system snapshots or wrapping ``borg serve`` to set special permissions or ACLs on new data files.