This special remote type stores file contents in a bucket in Amazon S3
or a similar service.

See [[tips/using_Amazon_S3]] and
[[tips/Internet_Archive_via_S3]] for usage examples.

## configuration

The standard environment variables `AWS_ACCESS_KEY_ID` and 
`AWS_SECRET_ACCESS_KEY` are used to supply login credentials
for Amazon. When encryption is enabled, they are stored in encrypted form
by `git annex initremote`. Without encryption, they are stored in a
file only you can read inside the local git repository. So you do not
need to keep the environment variables set after the initial
initalization of the remote.

A number of parameters can be passed to `git annex initremote` to configure
the S3 remote.

* `encryption` - Required. Either "none" to disable encryption
  (not recommended),
  or a value that can be looked up (using gpg -k) to find a gpg encryption
  key that will be given access to the remote. Note that additional gpg
  keys can be given access to a remote by rerunning initremote with
  the new key id. See [[encryption]].

* `datacenter` - Defaults to "US". Other values include "EU",
  "us-west-1", and "ap-southeast-1".

* `storageclass` - Default is "STANDARD". If you have configured git-annex
  to preserve multiple [[copies]], consider setting this to "REDUCED_REDUNDANCY"
  to save money.

* `host` and `port` - Specify in order to use a different, S3 compatable
  service.

* `bucket` - S3 requires that buckets have a globally unique name, 
  so by default, a bucket name is chosen based on the remote name
  and UUID. This can be specified to pick a bucket name.

* `fileprefix` - By default, git-annex places files in a tree rooted at the
  top of the S3 bucket. When this is set, it's prefixed to the filenames
  used. For example, you could set it to "foo/" in one special remote,
  and to "bar/" in another special remote, and both special remotes could
  then use the same bucket.

* `x-amz-*` are passed through as http headers when storing keys
  in S3.