systemd-imds-generator

systemd

Generator to automatically enable IMDS on supporting environments

/usr/lib/systemd/system-generators/systemd-imds-generator

Description

systemd-imds-generator is a generator that enables IMDS (Instance Metadata Service) functionality at boot on systems that support it. Specifically it does three things:

It pulls the systemd-imdsd.socket unit (which activates systemd-imdsd@.service(8)) into the initial transaction, which provides IMDS access to local applications via Varlink IPC.
It pulls the systemd-imds-early-network.service unit into the initial transaction, which generates a suitable systemd.network(5) network configuration file that allows early-boot network access to the IMDS functionality.
It pulls the systemd-imds-import.service unit into the initial transaction, which automatically imports various credentials from IMDS into the local system, storing them in /run/credstore/.

By default, whether to pull in these services or not is decided based on hwdb(7) information, that detects various IMDS environments automatically. However, this logic may be overridden via systemd.imds=, see below.

systemd-imds-generator implements systemd.generator(7).

Kernel Command Line

systemd-imds-generator understands the following kernel command line parameters:

systemd.imds=
Takes a boolean argument or the special value auto, and may be used to enable or disable the IMDS logic. Note that this controls only whether the relevant services (as listed above) are automatically pulled into the initial transaction, it has no effect if some other unit or the user explicitly activates the relevant units. If this option is not used (or set to auto) automatic detection of IMDS is used, see above.

systemd.imds.import=
Takes a boolean argument. If false the systemd-imds-import.service (see above) is not pulled into the initial transaction, i.e. no credentials are imported from IMDS. Defaults to true in the initrd, and false otherwise.