Capabilities¶

Setting a default locale
Setting an instance hostname
Generating instance SSH private keys
Adding SSH keys to a user’s .ssh/authorized_keys so they can log in
Setting up ephemeral mount points
Configuring network devices

User configurability¶

Cloud-init ‘s behavior can be configured via user-data.

User-data can be given by the user at instance launch time.

This is done via the --user-data or --user-data-file argument to ec2-run-instances for example.

Check your local clients documentation for how to provide a user-data string or user-data file for usage by cloud-init on instance creation.

Feature detection¶

Newer versions of cloud-init may have a list of additional features that they support. This allows other applications to detect what features the installed cloud-init supports without having to parse its version number. If present, this list of features will be located at cloudinit.version.FEATURES.

Currently defined feature names include:

NETWORK_CONFIG_V1 support for v1 networking configuration, see Networking Config Version 1 documentation for examples.

NETWORK_CONFIG_V2 support for v2 networking configuration, see Networking Config Version 2 documentation for examples.

CLI Interface :

cloud-init features will print out each feature supported. If cloud-init does not have the features subcommand, it also does not support any features described in this document.

% cloud-init --help
usage: cloud-init [-h] [--version] [--file FILES] [--debug] [--force]
                  {init,modules,query,single,dhclient-hook,features} ...

optional arguments:
  -h, --help            show this help message and exit
  --version, -v         show program's version number and exit
  --file FILES, -f FILES
                        additional yaml configuration files to use
  --debug, -d           show additional pre-action logging (default: False)
  --force               force running even if no datasource is found (use at
                        your own risk)

Subcommands:
  {init,modules,single,dhclient-hook,features,analyze,devel}
    init                initializes cloud-init and performs initial modules
    modules             activates modules using a given configuration key
    single              run a single module
    dhclient-hook       run the dhclient hookto record network info
    features            list defined features
    analyze             Devel tool: Analyze cloud-init logs and data
    devel               Run development tools

% cloud-init features
NETWORK_CONFIG_V1
NETWORK_CONFIG_V2