initial import

Documentation/coreos-init.md

@@ -0,0 +1,51 @@
+# coreos-init
+
+CoreOS allows a user to customize EC2 instances by providing either an executable script or a cloud-config document as instance user-data. See below to learn how to use these features.
+
+## cloud-config
+
+Only a subset of [cloud-config functionality][cloud-config] is implemented. A set of custom parameters were added to the cloud-config format that are specific to CoreOS.
+
+[cloud-config]: http://cloudinit.readthedocs.org/en/latest/topics/format.html#cloud-config-data
+
+### Supported cloud-config Parameters
+
+#### ssh_authorized_keys
+
+Provided public SSH keys will be authorized for the `core` user.
+
+### Custom cloud-config Parameters
+
+#### coreos.etcd.discovery_url
+
+The value of `coreos.etcd.discovery_url` will be used to discover the instance's etcd peers using the [etcd discovery protocol][disco-proto]. Usage of the [public discovery service][disco-service] is encouraged.
+
+[disco-proto]: https://github.com/coreos/etcd/blob/master/Documentation/discovery-protocol.md
+[disco-service]: http://discovery.etcd.io
+
+
+## user-data Script
+
+Simply set your user-data to a script where the first line is a shebang:
+
+```
+#!/bin/bash
+
+echo 'Hello, world!'
+```
+
+## Examples
+
+### Inject an SSH key and bootstrap an etcd cluster using cloud-config
+
+```
+#cloud-config
+
+coreos:
+	etcd:
+		discovery_url: https://discovery.etcd.io/827c73219eeb2fa5530027c37bf18877
+
+ssh_authorized_keys:
+  - ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC0g+ZTxC7weoIJLUafOgrm+h...
+```
+