M5 - Lesson 6: Managing virtual machines (Managing VM states (Off: A…
M5 - Lesson 6: Managing virtual machines
Managing VM states
A virtual machine that is off does not use any memory or processing resources.
A virtual machine that is starting verifies that resources are available before allocating those resources.
A virtual machine that is running uses the memory that has been allocated to it. It can also use the processing capacity that has been allocated to it.
A paused virtual machine does not consume any processing capacity but it does still retain the memory that has been allocated to it.
A saved virtual machine does not consume any memory or processing resources. The memory state for the virtual machine is saved as a file and is read when the virtual machine is started again.
Creating a checkpoint:
When creating checkpoints for multiple virtual machines that have dependencies, you should create them at the same time. This ensures synchronization of items such as computer account passwords. Remember that when you revert to a checkpoint, you are reverting to a computer’s state at that specific time. If you revert a computer back to a point before it performed a computer password change with a domain controller, you must rejoin that computer to the domain.
Checkpoints do not replace backups:
Checkpoint data is stored on the same volume as the virtual hard disk. If the volume that hosts these files fails, both the checkpoint and the virtual hard disk files are lost.
When you create a standard checkpoint, Hyper-V creates an .avhd file (differencing disk) that stores the data that differentiates the checkpoint from either the previous checkpoint or the parent virtual hard disk. When you delete standard checkpoints, this data is either discarded, or merged into the previous checkpoint or parent virtual hard disk.
Uses VSS. This places the virtual machine in a safe state to create a checkpoint that can be recovered in the same way as any VSS or application backup. Unlike standard checkpoints that save all memory and processing in the checkpoint, production checkpoints are closer to a state backup.
When you apply a checkpoint, the virtual machine reverts to the configuration that existed at the time that it took the checkpoint. Reverting to a checkpoint does not delete any existing checkpoints. If you revert to a checkpoint after making a configuration change, you receive a prompt to create a checkpoint. Creating a new checkpoint is necessary only if you want to return to that current configuration.
Register the virtual machine in-place:
This option creates a virtual machine by using the files in the existing location.
Restore the virtual machine:
This option copies the virtual machine files back to the location from which they were exported, and then creates a virtual machine by using the copied files.
Copy the virtual machine:
This option copies the virtual machine files to a new location that you can specify, and then creates a new virtual machine by using the copied files.
Export a checkpoint:
This enables you to create an exported virtual machine because it existed at the point of checkpoint creation. The exported virtual machine will have no checkpoints.
Export virtual machine with checkpoints:
This exports the virtual machine and all checkpoints that are associated with the virtual machine.
Move all the virtual machine’s data to a single location:
This moves all configuration files, checkpoints, and virtual hard-disk files to the destination location.
Move the virtual machine’s data to different locations:
This moves the virtual machine’s configuration files, checkpoints, and virtual hard disks to separate locations.
Move the virtual machine’s virtual hard disks:
This moves the hard disks to a separate location while keeping the checkpoint and configuration files in the same location.
Does not require network connectivity
Can only be used from the host to the virtual machine