git-annex/doc/walkthrough/using_ddar.mdwn

Another [[special_remote|special_remotes]] that git-annex can use is
a [[special_remotes/ddar]] repository. ddar stores large file contents
in a directory structure of its own, with deduplication. For remote
repositories, ddar requires that ssh is available on the remote, with ddar also
installed remotely. When copying files to the remote, ddar only needs to send
over the network the parts of the files that are not already present remotely.

Unlike bup, ddar uses its own storage format, which allows for both creation
and deletion of de-deduplicated files.

Here's how to create a ddar remote, and describe it.

[[!template id=note text="""
Instead of specifying a remote system, you could choose to make a ddar
remote that is only accessible on the current system, by passing
"ddarrepo=/big/myddar".
"""]]

	$ git annex initremote myddar type=ddar encryption=none ddarrepo=example.com:/big/myddar
	initremote ddar (ddar init)
	Initialized empty Git repository in /big/myddar/
	ok
	$ git annex describe myddar "my ddar repository at example.com"
	describe myddar ok

Now the remote can be used like any other remote.

	$ git annex move my_cool_big_file --to myddar
	move my_cool_big_file (to myddar...)
	ok

See [[special_remotes/ddar]] for details.