The communication between oVirt guest agent and the oVirt engine

The engine directs requests for the guest agent to VDSM.

VDSM communicates with the guest using a VirtIO channel using plain text commands in JSON format. Each command is terminated by a new line character.

VDSM/Guest Agent message structure

Each message sent by VDSM has a mandatory field __name__ which contains the command name.

All additional fields in the message are considered arguments to the command.