This developer documentation is outdated, but provides historical context.

It is not user documentation and should not be treated as such.

Documentation is available here.


The agent is an application which run as a background process inside the guest, it communicates with Vdsm over a vioserial device. It provides:


The agent provides the following information:

  • Machine name – Show the virtual machine’s host name.
  • Operating system version – Show the operating system’s version. Linux: this value is the kernel version. Windows: it is the Windows version name (e.g. Windows XP or Windows 7).
  • Installed applications – List in installed applications. Linux: application list is set using the configuration file. Windows: installed applications list is based on value read from registry.
  • Available RAM – The amount of unused physical memory. This value probably includes memory like cache, or else the memory usage will always be (or near) 100% usage.
  • Logged in users – List of all logged-in users.
  • Active user – The user that is currently using the virtual machine’s “physical hardware”. Redundant because RHEV-M is treating the SPICE’s ticket owner as the active user.
  • Disks usage – VM disks utilization.
  • Network interfaces – Internal guest network mapping (MAC, name, ipv4, ipv6).
  • FQDN – Reports the configured (F)ully (Q)ualified (D)omain (N)ame of the guest os


The agent notify on the following events:

  • Power up – Sent when the agent is started.
  • Power down – Unused.
  • Heartbeat – The message sent every few second to notify that the agent is running. The notification includes the guest’s available RAM.
  • User info – Active user has changed.
  • Session lock – Desktop was locked (Windows).
  • Session unlock – Desktop was unlocked (Windows).
  • Session logoff – A user was logged off (Windows).
  • Session logon – A user was logged on (Windows).
  • Agent uninstalled – Agent was removed from the system. This is not sent by the agent itself but by the agent’s (un-)installer.


The following actions can be requested from the agent: