Plugins

Plugins execute actions based on the metadata obtained by the loaded service. They are intended to actually configure your instance using data provided by the cloud and even by the user. There are three stages for the plugins execution:

1. The pre-networking stage (for setting up the network, before doing any valid web request).

2. The pre-metadata-discovery one (additional configuration before the metadata service discovery).

3. The main set of plugins, which holds the rest of the plugins which are (re)executed according to their saved status.

Note that the first two stages (1,2) are executed each time the service starts.

Current list of supported plugins:

Setting host name (main)

class cloudbaseinit.plugins.common.sethostname.SetHostNamePlugin

Sets the instance’s hostname. It may be truncated to 15 characters for Netbios compatibility reasons using the option below.

Config options:

  • netbios_host_name_compatibility (bool: True)

Warning

This may require a system restart.

Creating user (main)

class cloudbaseinit.plugins.windows.createuser.CreateUserPlugin

Creates (or updates if existing) a new user and adds it to a set of provided local groups. By default, it creates the user “Admin” under “Administrators” group, but this can be changed under configuration file.

Config options:

  • username (string: “Admin”)
  • groups (list of strings: [“Administrators”])

Setting password (main)

class cloudbaseinit.plugins.windows.setuserpassword.SetUserPasswordPlugin

Sets the cloud user’s password. If a password has been provided in the metadata during boot it will be used, otherwise a random password will be generated, encrypted with the user’s SSH public key and posted to the metadata provider (currently supported only by the OpenStack HTTP metadata provider). An option called inject_user_password is set True by default to make available the use of metadata password which is found under the “admin_pass” field or through an URL request. If the option is set to False or if the password isn’t found in metadata, then an attempt of using an already set password is done (usually a random value by the createuser plugin). With first_logon_behaviour you can control what happens with the password at the next logon. If this option is set to “always”, the user will be forced to change the password at the next logon. If it is set to “clear_text_injected_only”, the user will be forced to change the password only if the password is a clear text password, coming from the metadata. The last option is “no”, when the user is never forced.

Config options:

  • inject_user_password (bool: True)
  • first_logon_behaviour (string: “clear_text_injected_only”)

Note

This plugin can run multiple times (for posting the password if the metadata service supports this).

Static networking (main)

class cloudbaseinit.plugins.common.networkconfig.NetworkConfigPlugin

Statically configures each network adapter for which corresponding details are found into metadata. The details/addresses association is done using MAC matching and if this fails, then name or interface index matching. The basic setting is based on IPv4 addresses, but it supports IPv6 addresses too if they are enabled and exposed to the metadata. The purpose of this plugin is to configure network adapters, for which the DHCP server is disabled, to have internet access and static IPs.

Warning

This may require a system restart.

Saving public keys (main)

class cloudbaseinit.plugins.common.sshpublickeys.SetUserSSHPublicKeysPlugin

Creates an authorized_keys file in the user’s home directory containing the SSH keys provided in the metadata. It is needed by the plugin responsible for encrypting and setting passwords.

Config options:

  • username (string: “Admin”)

Volume expanding (main)

class cloudbaseinit.plugins.windows.extendvolumes.ExtendVolumesPlugin

Extends automatically a disk partition to its maximum size. This is useful when booting images with different flavors. By default, all the volumes are extended, but you can select specific ones by populating with their indexes the volumes_to_extend option.

Config options:

  • volumes_to_extend (list of integers: None)

Note

This plugin will run at every boot.

WinRM listener (main)

class cloudbaseinit.plugins.windows.winrmlistener.ConfigWinRMListenerPlugin

Configures a WinRM HTTPS listener to allow remote management via WinRM or PowerShell.

Config options:

  • winrm_enable_basic_auth (bool: True)

Note

This plugin will run until a full and proper configuration will take place.

WinRM certificate (main)

class cloudbaseinit.plugins.windows.winrmcertificateauth.ConfigWinRMCertificateAuthPlugin

Enables password-less authentication for remote management via WinRS or PowerShell. Usually uses x509 embedded with UPN certificates.

Config options:

  • username (string: “Admin”)

Scripts execution (main)

class cloudbaseinit.plugins.common.localscripts.LocalScriptsPlugin

Executes any script (powershell, batch, python etc.) located in the following path indicated by local_scripts_path option. More details about the supported scripts and content can be found in Tutorial on file execution subject.

Config options:

  • local_scripts_path (string: None)

Warning

This may require a system restart.

Note

This plugin may run multiple times (depending on the script(s) return code).

Licensing (main)

class cloudbaseinit.plugins.windows.licensing.WindowsLicensingPlugin

Activates the Windows instance if the activate_windows option is True.

Config options:

  • activate_windows (bool: False)

Clock synchronization (pre-networking)

class cloudbaseinit.plugins.windows.ntpclient.NTPClientPlugin

Applies NTP client info based on the DHCP server options, if available. This behavior is enabled only when the ntp_use_dhcp_config option is set to True (which by default is False).

Config options:

  • ntp_use_dhcp_config (bool: False)

Note

This plugin will run until the NTP client is configured.

MTU customization (pre-metadata-discovery)

class cloudbaseinit.plugins.common.mtu.MTUPlugin

Sets the network interfaces MTU based on the value provided by the DHCP server options, if available and enabled (by default is True). This is particularly useful for cases in which a lower MTU value is required for networking (e.g. OpenStack GRE Neutron Open vSwitch configurations).

Config options:

  • mtu_use_dhcp_config (bool: True)

Note

This plugin will run at every boot.

User data (main)

class cloudbaseinit.plugins.common.userdata.UserDataPlugin

Executes custom scripts provided by user data metadata as plain text or compressed with Gzip. More details, examples and possible formats here: Userdata.


Configuring selected plugins

By default, all plugins are executed, but a custom list of them can be specified through the plugins option in the configuration file.

For more details on doing this, see configuration file in Tutorial.