Datasources are sources of configuration data for cloud-init that typically come from the user (i.e., user data) or come from the cloud that created the configuration drive (i.e., metadata). Typical user data includes files, YAML, and shell scripts whereas typical metadata includes server name, instance id, display name, and other cloud specific details.

Any metadata processed by cloud-init’s datasources is persisted as /run/cloud-init/instance-data.json. Cloud-init provides tooling to quickly introspect some of that data. See Instance metadata for more information.

How to configure which datasource to use

By default cloud-init should automatically determine which datasource it is running on. Therefore, in most cases, users of cloud-init should not have to configure cloud-init to specify which datasource cloud-init is running on; cloud-init should “figure it out”.

There are exceptions, however, when the datasource does not identify itself to cloud-init. For these exceptions, one can override datasource detection either by configuring a single datasource in the datasource_list, or by using kernel command line arguments.


The following is a list of documentation for each supported datasource: