Scaleway User Data API

User data is a key/value store you can use to provide your instance with introspective data.As an example of use, Scaleway images contain the `scw-generate-ssh-keys` script, which generates the SSH server’s host keys, then stores their fingerprints as user data under the `ssh-host-fingerprints` key.This way, before connecting to the instance using SSH, one can query the fingerprints to ensure that the remote host is the expected one, thus avoiding any man-in-the-middle attack.There are two ways of accessing user data: - **From within a running Instance**, by requesting the Metadata API at http://169.254.42.42/user_data(or http://[fd00:42::42]/user_data using IPv6). The `scaleway-ecosystem` package, installed by default on all OS images provided by Scaleway, shipswith the `scw-userdata` helper command that allows you to easily query the user data from the instance. For security reasons, viewing and editing user data is only allowed to queries originating froma port below 1024 (by default, only the super-user can bind to ports below 1024). To specify the source port with cURL, use the `--local-port` option (e.g. `curl --local-port 1-1023http://169.254.42.42/user_data`). - **From the Instance API** by using the methods described below.