git-annex/doc/walkthrough/using_ssh_remotes.mdwn

So far in this walkthrough, git-annex has been used with a remote
repository on a USB drive. But it can also be used with a git remote
that is truly remote, a host accessed by ssh.

Say you have a desktop on the same network as your laptop and want
to clone the laptop's annex to it:

	desktop$ git clone ssh://mylaptop/home/me/annex ~/annex
	desktop$ cd ~/annex
	desktop$ git annex init "my desktop"

Now you can get files and they will be transferred (using `rsync` via `ssh`):

	desktop$ git annex get my_cool_big_file
	get my_cool_big_file (getting UUID for origin...) (from origin...)
	SHA256-s86050597--6ae2688bc533437766a48aa19f2c06be14d1bab9c70b468af445d4f07b65f41e  100% 2159     2.1KB/s   00:00
	ok

When you drop files, git-annex will ssh over to the remote and make
sure the file's content is still there before removing it locally:

	desktop$ git annex drop my_cool_big_file
	drop my_cool_big_file (checking origin..) ok

Note that normally git-annex prefers to use non-ssh remotes, like
a USB drive, before ssh remotes. They are assumed to be faster/cheaper to
access, if available. There is a annex-cost setting you can configure in
`.git/config` to adjust which repositories it prefers. See
[[the_man_page|git-annex]] for details.

Also, note that you need full shell access for this to work -- 
git-annex needs to be able to ssh in and run commands. Or at least,
your shell needs to be able to run the [[git-annex-shell]] command.

For details on setting up ssh remotes, see the
[[tips/centralized_git_repository_tutorial]].
split the walkthrough and inline back together 2011-02-27 16:45:48 +00:00			`So far in this walkthrough, git-annex has been used with a remote`
			`repository on a USB drive. But it can also be used with a git remote`
typo 2013-07-21 04:44:19 +00:00			`that is truly remote, a host accessed by ssh.`
split the walkthrough and inline back together 2011-02-27 16:45:48 +00:00
			`Say you have a desktop on the same network as your laptop and want`
			`to clone the laptop's annex to it:`

this is not all run as root 2019-03-27 15:15:03 +00:00			`desktop$ git clone ssh://mylaptop/home/me/annex ~/annex`
			`desktop$ cd ~/annex`
			`desktop$ git annex init "my desktop"`
split the walkthrough and inline back together 2011-02-27 16:45:48 +00:00
be more clear about the rsync usage 2011-03-06 16:32:16 +00:00			Now you can get files and they will be transferred (using `rsync` via `ssh`):
split the walkthrough and inline back together 2011-02-27 16:45:48 +00:00
this is not all run as root 2019-03-27 15:15:03 +00:00			`desktop$ git annex get my_cool_big_file`
get --from is the same as copy --from get not honoring --from has surprised me a few times, so least surprise suggests it should just behave like copy --from. This leaves the difference between get and copy being that copy always requires the remote to copy from, while get will decide whether to get a file from a key/value store or a remote. 2011-06-09 22:54:49 +00:00			`get my_cool_big_file (getting UUID for origin...) (from origin...)`
use SHA256 by default To get old behavior, add a .gitattributes containing: * annex.backend=WORM I feel that SHA256 is a better default for most people, as long as their systems are fast enough that checksumming their files isn't a problem. git-annex should default to preserving the integrity of data as well as git does. Checksum backends also work better with editing files via unlock/lock. I considered just using SHA1, but since that hash is believed to be somewhat near to being broken, and git-annex deals with large files which would be a perfect exploit medium, I decided to go to a SHA-2 hash. SHA512 is annoyingly long when displayed, and git-annex displays it in a few places (and notably it is shown in ls -l), so I picked the shorter hash. Considered SHA224 as it's even shorter, but feel it's a bit weird. I expect git-annex will use SHA-3 at some point in the future, but probably not soon! Note that systems without a sha256sum (or sha256) program will fall back to defaulting to SHA1. 2011-11-04 19:21:45 +00:00			`SHA256-s86050597--6ae2688bc533437766a48aa19f2c06be14d1bab9c70b468af445d4f07b65f41e 100% 2159 2.1KB/s 00:00`
split the walkthrough and inline back together 2011-02-27 16:45:48 +00:00			`ok`

			`When you drop files, git-annex will ssh over to the remote and make`
			`sure the file's content is still there before removing it locally:`

this is not all run as root 2019-03-27 15:15:03 +00:00			`desktop$ git annex drop my_cool_big_file`
split the walkthrough and inline back together 2011-02-27 16:45:48 +00:00			`drop my_cool_big_file (checking origin..) ok`

			`Note that normally git-annex prefers to use non-ssh remotes, like`
			`a USB drive, before ssh remotes. They are assumed to be faster/cheaper to`
			`access, if available. There is a annex-cost setting you can configure in`
			`.git/config` to adjust which repositories it prefers. See
			`[[the_man_page\|git-annex]] for details.`

			`Also, note that you need full shell access for this to work --`
			`git-annex needs to be able to ssh in and run commands. Or at least,`
			`your shell needs to be able to run the [[git-annex-shell]] command.`
link to the centralized_git_repository_tutorial 2015-08-05 18:15:20 +00:00
			`For details on setting up ssh remotes, see the`
			`[[tips/centralized_git_repository_tutorial]].`