git-annex(1)

NAME
git-annex - manage files with git, without checking their contents in

SYNOPSIS
git annex command [params ...]

DESCRIPTION
git-annex allows managing files with git, without checking the file contents into git. While that may seem paradoxical, it is useful when dealing with files larger than git can currently easily handle, whether due to limitations in memory, checksumming time, or disk space.

Even without file content tracking, being able to manage files with git, move files around and delete files with versioned directory trees, and use branches and distributed clones, are all very handy reasons to use git. And annexed files can co-exist in the same git repository with regularly versioned files, which is convenient for maintaining documents, Makefiles, etc that are associated with annexed files but that benefit from full revision control.

When a file is annexed, its content is moved into a key-value store, and a symlink is made that points to the content. These symlinks are checked into git and versioned like regular files. You can move them around, delete them, and so on. Pushing to another git repository will make git-annex there aware of the annexed file, and it can be used to retrieve its content from the key-value store.

EXAMPLES
 # git annex get video/hackity_hack_and_kaxxt.mov
 get video/_why_hackity_hack_and_kaxxt.mov (not available)
   I was unable to access these remotes: server
   Try making some of these repositories available:
       5863d8c0-d9a9-11df-adb2-af51e6559a49 -- my home file server
        58d84e8a-d9ae-11df-a1aa-ab9aa8c00826 -- portable USB drive
        ca20064c-dbb5-11df-b2fe-002170d25c55 -- backup SATA drive
 failed
 # sudo mount /media/usb
 # git remote add usbdrive /media/usb
 # git annex get video/hackity_hack_and_kaxxt.mov
 get video/hackity_hack_and_kaxxt.mov (from usbdrive...) ok
 # git commit -a -m "got a video I want to rewatch on the plane"

 # git annex add iso
 add iso/Debian_5.0.iso ok
 # git commit -a -m "saving Debian CD for later"

 # git annex drop iso/Debian_4.0.iso
 drop iso/Debian_4.0.iso ok
 # git commit -a -m "freed up space"

 # git annex move iso --to=usbdrive
 move iso/Debian_5.0.iso (moving to usbdrive...) ok

COMMANDS
Like many git commands, git-annex can be passed a path that is either a file or a directory. In the latter case it acts on all relevant files in the directory. If no path is specified, most git-annex commands default to acting on all relevant files in the current directory (and subdirectories).

Many git-annex commands will stage changes for later git commit by you.

add [path ...]
    Adds files in the path to the annex. Files that are already checked into git, or that git has been configured to ignore will be silently skipped.

get [path ...]
    Makes the content of annexed files available in this repository. Depending on the backend used, this will involve copying them from another repository, or downloading them, or transferring them from some kind of key-value store.

drop [path ...]
    Drops the content of annexed files from this repository.

    git-annex may refuse to drop content if the backend does not think it is safe to do so, typically because of the setting of annex.numcopies.

move [path ...]
    When used with the --from option, moves the content of annexed files from the specified repository to the current one.

    When used with the --to option, moves the content of annexed files from the current repository to the specified one.

copy [path ...]
    When used with the --from option, copies the content of annexed files from the specified repository to the current one.

    When used with the --to option, copies the content of annexed files from the current repository to the specified one.

    To avoid contacting the remote to check if it has every file, specify --fast

unlock [path ...]
    Normally, the content of annexed files is protected from being changed. Unlocking a annexed file allows it to be modified. This replaces the symlink for each specified file with a copy of the file's content. You can then modify it and git annex add (or git commit) to inject it back into the annex.

edit [path ...]
    This is an alias for the unlock command. May be easier to remember, if you think of this as allowing you to edit an annexed file.

lock [path ...]
    Use this to undo an unlock command if you don't want to modify the files, or have made modifications you want to discard.

init description
    Initializes git-annex with a description of the git repository, and sets up .gitattributes and the pre-commit hook.

describe repository description
    Changes the description of a repository.

    The repository to describe can be specified by git remote name or by uuid. To change the description of the current repository, use "."

initremote name [param=value ...]
    Sets up a special remote. The remote's configuration is specified by the parameters. If a remote with the specified name has already been configured, its configuration is modified by any values specified. In either case, the remote will be added to .git/config.

    Example Amazon S3 remote:

     initremote mys3 type=S3 encryption=none datacenter=EU

fsck [path ...]
    With no parameters, this command checks the whole annex for consistency, and warns about or fixes any problems found.

    With parameters, only the specified files are checked.

    To avoid expensive checksum calculations, specify --fast

unused
    Checks the annex for data that does not correspond to any files present in the currently checked out branch, and prints a numbered list of the data.

    To only show unused temp and bad files, specify --fast

    To check data on a remote that does not correspond to any files present on the locally checked out branch, specify --from.

dropunused [number ...]
    Drops the data corresponding to the numbers, as listed by the last git annex unused

    To drop the data from a remote, specify --from.

find [path ...]
    Outputs a list of annexed files whose content is currently present.

    With no parameters, defaults to finding all files in the current directory and its subdirectories.

whereis [path ...]
    Displays a list of repositories known to contain the content of the specified file or files.

merge
    Automatically merges any changes from remotes into the git-annex branch. While git-annex mostly handles keeping the git-annex branch merged automatically, if you find you are unable to push the git-annex branch due non-fast-forward, this will fix it.

status
    Displays some statistics and other information, including how much data is in the annex.

    Some of the statistics can take a while to generate, and those come last. You can ctrl-c this command once it's displayed the information you wanted to see. Or, use --fast to only display the first, fast(ish) statistics.

migrate [path ...]
    Changes the specified annexed files to store their content in the default backend (or the one specified with --backend). Only files whose content is currently available are migrated.

    Note that the content is not removed from the backend it was previously in. Use git annex unused to find and remove such content.

    Normally, nothing will be done to files already in the backend. However, if a backend changes the information it uses to construct a key, this can also be used to migrate files to use the new key format.

map Helps you keep track of your repositories, and the connections between them, by going out and looking at all the ones it can get to, and generating a Graphviz file displaying it all. If the dot command is available, it is used to display the file to your screen (using x11 backend).

    Note that this only connects to hosts that the host it's run on can directly connect to. It does not try to tunnel through intermediate hosts. So it might not show all connections between the repositories in the network.

    Also, if connecting to a host requires a password, you might have to enter it several times as the map is being built.

    Note that this subcommand can be used to graph any git repository; it is not limited to git-annex repositories.

unannex [path ...]
    Use this to undo an accidental git annex add command. You can use git annex unannex to move content out of the annex at any point, even if you've already committed it.

    This is not the command you should use if you intentionally annexed a file and don't want its contents any more. In that case you should use git annex drop instead, and you can also git rm the file.

    In --fast mode, this command leaves content in the annex, simply making a hard link to it.

uninit
    Use this to stop using git annex. It will unannex every file in the repository, and remove all of git-annex's other data, leaving you with a git repository plus the previously annexed files.

fix [path ...]
    Fixes up symlinks that have become broken to again point to annexed content. This is useful to run if you have been moving the symlinks around.

pre-commit [path ...]
    Fixes up symlinks that are staged as part of a commit, to ensure they point to annexed content. Also handles injecting changes to unlocked files into the annex.

    This is meant to be called from git's pre-commit hook. git annex init automatically creates a pre-commit hook using this.

trust [repository ...]
    Records that a repository is trusted to not unexpectedly lose content. Use with care.

    To trust the current repository, use "."

untrust [repository ...]
    Records that a repository is not trusted and could lose content at any time.

semitrust [repository ...]
    Returns a repository to the default semi trusted state.

addurl [url ...]
    Downloads each url to a file, which is added to the annex.

fromkey file
    This plumbing-level command can be used to manually set up a file to link to a specified key in the key-value backend.

dropkey [key ...]
    This plumbing-level command drops the annexed data for the specified keys from this repository.

    This can be used to drop content for arbitrary keys, which do not need to have a file in the git repository pointing at them.

    Example:

     git annex dropkey SHA1-s10-7da006579dd64330eb2456001fd01948430572f2

setkey file
    This plumbing-level command sets the annexed data for a key to the content of the specified file, and then removes the file.

    Example:

     git annex setkey --key=WORM-s3-m1287765018--file /tmp/file

upgrade
    Upgrades the repository to current layout.

version
    Shows the version of git-annex, as well as repository version information.

OPTIONS

--force

    Force unsafe actions, such as dropping a file's content when no other source of it can be verified to still exist, or adding ignored files. Use with care.

--fast
    Enables less expensive, but also less thorough versions of some commands. What is avoided depends on the command.

--quiet
    Avoid the default verbose logging of what is done; only show errors and progress displays.

--verbose
    Enable verbose logging.

--debug
    Show debug messages.

--from=repository
    Specifies a repository that content will be retrieved from, or that should otherwise be acted on.

    It should be specified using the name of a configured remote.

--to=repository
    Specifies a repository that content will be sent to.

    It should be specified using the name of a configured remote.

--exclude=glob
    Skips files matching the glob pattern. The glob is matched relative to the current directory.

    This option can be specified multiple times.

--numcopies=n
    Overrides the annex.numcopies setting, forcing git-annex to ensure the specified number of copies exist.

--trust=repository

--semitrust=repository

--untrust=repository
    Overrides trust settings for a repository. May be specified more than once.

    The repository should be specified using the name of a configured remote, or the UUID or description of a repository.

--backend=name
    Specifies which key-value backend to use. This can be used when adding a file to the annex, or migrating a file. Once files are in the annex, their backend is known and this option is not necessary.

--key=name
    Specifies a key to operate on.

CONFIGURATION
Like other git commands, git-annex is configured via .git/config. Here are all the supported configuration settings.

annex.uuid
    A unique UUID for this repository (automatically set).

annex.numcopies
    Number of copies of files to keep across all repositories. (default: 1)

annex.backends
    Space-separated list of names of the key-value backends to use. The first listed is used to store new files by default.

remote.<name>.annex-cost
    When determining which repository to transfer annexed files from or to, ones with lower costs are preferred. The default cost is 100 for local repositories, and 200 for remote repositories.

remote.<name>.annex-ignore
    If set to true, prevents git-annex from using this remote by default. (You can still request it be used by the --from and --to options.)

    This is, for example, useful if the remote is located somewhere without git-annex-shell. (For example, if it's on GitHub). Or, it could be used if the network connection between two repositories is too slow to be used normally.

remote.<name>.annex-uuid
    git-annex caches UUIDs of remote repositories here.

remote.<name>.annex-ssh-options
    Options to use when using ssh to talk to this remote.

remote.<name>.annex-rsync-options
    Options to use when using rsync to or from this remote. For example, to force ipv6, and limit the bandwidth to 100Kbyte/s, set it to "-6 --bwlimit 100"

remote.<name>.annex-bup-split-options
    Options to pass to bup split when storing content in this remote. For example, to limit the bandwidth to 100Kbye/s, set it to "--bwlimit 100k" (There is no corresponding option for bup join.)

annex.ssh-options, annex.rsync-options, annex.bup-split-options
    Default ssh, rsync, and bup options to use if a remote does not have specific options.

annex.diskreserve
    Amount of disk space to reserve. Disk space is checked when transferring content to avoid running out, and additional free space can be reserved via this option, to make space for more important content (such as git commit logs). Can be specified with any commonly used units, for example, "0.5 gb" or "100 KiloBytes"

    The default reserve is 1 megabyte.

annex.version
    Automatically maintained, and used to automate upgrades between versions.

remote.<name>.buprepo
    Used by bup special remotes, this configures the location of the bup repository to use. Normally this is automaticaly set up by git annex initremote, but you can change it if needed.

remote.<name>.directory
    Used by directory special remotes, this configures the location of the directory where annexed files are stored for this remote. Normally this is automaticaly set up by git annex initremote, but you can change it if needed.

remote.<name>.s3
    Used to identify Amazon S3 special remotes. Normally this is automaticaly set up by git annex initremote.

CONFIGURATION VIA .gitattributes
The backend used when adding a new file to the annex can be configured on a per-file-type basis via .gitattributes files. In the file, the annex.backend attribute can be set to the name of the backend to use. For example, this here's how to use the WORM backend by default, but the SHA1 backend for ogg files:

 * annex.backend=WORM
 *.ogg annex.backend=SHA1

The numcopies setting can also be configured on a per-file-type basis via the annex.numcopies attribute in .gitattributes files. For example, this makes two copies be needed for wav files:

 *.wav annex.numcopies=2

FILES
These files are used by git-annex, in your git repository:

.git/annex/objects/ contains the annexed file contents that are currently available. Annexed files in your git repository symlink to that content.

SEE ALSO
Most of git-annex's documentation is available on its web site, <http://git-annex.branchable.com/>

If git-annex is installed from a package, a copy of its documentation should be included, in, for example, /usr/share/doc/git-annex/

AUTHOR
Joey Hess <joey@kitenet.net>

<http://git-annex.branchable.com/>