Chapter 6: Maintaining a Hyper-V Environment
Explain how backup works in a Hyper-V environment. Windows features the
VSS component that enables application-consistent backups to be taken of an
operating system by calling VSS writers created by application vendors. When a
backup is taken of a virtual machine at the Hyper-V host level, the VSS request is
passed to the guest operating system via the backup guest service, which allows the
guest OS to ensure that the disk is in a backup-ready state, allowing the virtual hard
disk to be backed up at the host and be application consistent.
Master It Is shared VHDX backed up when you perform a VM backup at the host
level?
Solution No. Shared VHDX, iSCSI, and Fibre Channel–connected storage are not
backed up when performing a VM backup at the host level. To back up these types
of storage, a backup within the virtual machine must be performed. If VHD Sets are
used, which are the Windows Server 2016 implementation of Shared VHDX, then
the VHD Set content is backed up when performing a host-level backup.Understand how to best use checkpoints and where not to use them.
Checkpoints, previously known as snapshots, allow a point-in-time view of a virtual
machine to be captured and then applied at a later time to revert the virtual machine
back to the state it was in at the time the snapshot was taken. Windows Server 2016
introduced a new type of checkpoint, the production checkpoint. Production
checkpoints interact with the VSS infrastructure inside the guest OS that provides an
application-consistent checkpoint. Production checkpoints can be used in production
environments. Standard checkpoints that do not interact with VSS and save the
complete state of a VM, including memory, are useful in testing scenarios but should
not be used in production, because the effect of moving a virtual machine back in time
without the OS knowledge can cause problems for many services. It can even cause
domain membership problems if the computer’s AD account password changes after
the checkpoint creation.
Understand the benefits of service templates. Typically, a virtual machine is
created from a virtual machine template, which allows a single virtual machine to be
deployed. A service template allows a complete, multitiered service to be designed and
then deployed through a single action. Additionally, each tier can be configured to
scale up and down as workloads vary, which enables additional instances of the virtual
machine for a tier to be created and deleted as necessary. Deployed instances of a
service template retain their relationship to the original service template, which
means that if the original service template is updated, the deployed instances can be
refreshed and updated with the service template changes without losing application
state.