5.4. About Desktop and Virtual Machine States

5.4.1. Virtual Machine States
5.4.2. Desktop States

In Oracle VDI, a user is assigned to one or several virtual desktops and can use these desktops from everywhere as if they were running on a traditional personal computer. Oracle VDI provides advanced management and lifecycle features which allow the effective management of thousands of desktops. Desktops transition through states defined by settings in Oracle VDI.

Virtual machines are used to run the operating systems which render the desktops. They are controlled by a hypervisor, such as Oracle VM VirtualBox, Microsoft Hyper-V, and VMware Infrastructure. They cycle through traditional machine states such as powered off and running.

5.4.1. Virtual Machine States

Virtual machine states are defined by the virtualization platform.

  • Running

    Running desktops are registered and started on a single hypervisor host. The host that a virtual machine is running on can be determined using the Desktop Summary page in Oracle VDI Manager. A running virtual machine is connected directly to the storage.

  • Powered Off

    Powered off virtual machines reside in two places in the Oracle VDI environment, the database and the storage. The Oracle VDI database contains the desktop configuration information to register the desktop on a hypervisor. The storage server contains the desktop's hard disk data.

    Powered off virtual machines are typically not associated or registered on any hypervisor host. This strategy enables Oracle VDI to select the best suited host on every start of a virtual machine. This setup helps ensure a distribution of virtual machines across the available VirtualBox or Microsoft Hyper-V hosts minimizing resource usage on each.

  • Suspended

    Suspended virtual machines have been suspended by the hypervisor.

  • Paused, Aborted, or Stuck

    These machine states are specific to VirtualBox.

  • Unknown

    This state typically indicates that either a VMware vCenter server cannot be contacted to retrieve the state information, or a VirtualBox host returns null.

  • Active or Disconnected

    These machine states apply to Microsoft Remote Desktops only. Oracle VDI does not control the machine state, just the connection to the desktop.

5.4.2. Desktop States

The desktop states are used to accomplish the following:

  • Implement the desktop lifecycle.

  • Synchronize Oracle VDI hosts and virtualization platform.

  • Serve as a tool for monitoring and analyzing the system state.

The following figure depicts a simplified version of the lifecycle of a flexibly assigned desktop.

Figure 5.2. Lifecycle of a Flexibly-Assigned Desktop

The diagram shows the lifecycle of a desktop, from being cloned from a template, then alternating between the used and idle states, and then finally being recycled or deleted.

Possible desktop states are:

  • Available - The first state

    A desktop is added to the database and then set to the Available state after being cloned from a template. After becoming Available, the desktop is ready to be assigned to users. If the recycle policy is set to Reuse Desktop or Reset to Snapshot, the desktop will return to this state.

  • Idle - The intermediate state

    The desktop is in this state whenever the desktop is assigned and the user is not using it, for example, when the desktop is assigned and the user has not logged in yet or when the desktop is assigned and the user just logged out. A desktop is recycled after it remains in that state for a configurable amount of time.

    The VMware vCenter desktop provider has two additional Idle states: when the desktop is assigned and either the virtual machine is suspended or the guest OS goes into standby through the vCenter option Keep VM Running on Guest OS Standby.

  • Used - The active state

    A desktop enters the Used state as soon as the user has logged in to the desktop. The desktop stays in this state while the user logs in, uses the desktop, and logs out.

  • Reserved - The maintenance state

    A desktop is Reserved when it is being worked on by Oracle VDI. This desktop state usually occurs when the desktop is the source of a manual copy operation or the desktop is recycled. The desktop will become Available after leaving the Reserved state.

  • Unresponsive - The quarantine state

    The desktop enters the Unresponsive state whenever Oracle VDI determines a severe problem with the desktop. An unresponsive desktop is outside the desktop life cycle and needs the attention of the administrator. The administrator may either fix the problem and apply the Activate action to the desktop, which puts the desktop back in the lifecycle, or the administrator may choose to delete the desktop.