Backing Up Virtual Machines

Table Of Contents

 You want to back up cluster nodes before installing software updates on them.

In this scenario, install both Agent for Hyper-V and Agent for Windows on each node of the cluster.

Set up disk-level backups for both nodes, by creating a centralized backup plan. You can exclude

virtual machines from the backup, by excluding the CSV where the machines are stored from the CSV

owner backup. Volumes that correspond to CSV do not have letters, so you can easily recognize

them.

Before installing the software updates, back up the nodes. Install the software updates on one node

at a time. If installing the updates has caused problems with the operating system, turn off the node.

The remaining nodes will take over the virtual machines that ran on the node. Use the bootable

media to recover the node. Once the node is operational again, the virtual machines will migrate

back to it.

To back up the virtual machines themselves, create a separate backup plan. For details, see "Backing

up clustered Hyper-V machines" (p. 25).

3.5.5 Support for Hyper-V 3.0

This section describes how Acronis Backup supports new features introduced in Hyper-V 3.0. This

version of Hyper-V appears in Windows Server 2012.

VHDX format

The VHDX format appeared in Hyper-V 3.0 as a new version of the virtual hard disk (VHD) format. The

VHDX format supports a maximum disk size of 64 TB, compared with the maximum size of 2 TB for

VHD. The VHDX format also supports disks with a physical and/or logical sector size of 4 KB.

Agent for Hyper-V can back up and recover virtual machines whose disks have the VHDX format.

When recovering a virtual machine from a Hyper-V host of an earlier version to a Hyper-V 3.0 host,

the agent converts the machine's disks to the VHDX format.

When recovering a virtual machine with VHDX disks to a Hyper-V host of an earlier version, the agent

converts the disks to the VHD format. The agent tries to make the resulting disk meet the

requirements of the VHD format. For example, if the source VHDX disk is greater than 2 TB, the agent

attempts to reduce the resulting VHD disk size to 2 TB.

Dynamic Memory

Dynamic Memory adjusts the original amount of the virtual machine's memory depending on the

machine's actual memory needs. Agent for Hyper-V can back up and recover virtual machines that

use the Dynamic Memory feature. However, the agent does not save the Dynamic Memory settings

for these machines.

When recovering a machine to a new virtual machine, the agent sets up the original amount of

memory for it. The Dynamic Memory feature for the recovered machine will be turned off.

Private VLANs

Private virtual local area networks (private VLANs, PVLANs) enable you to isolate groups of virtual

machines on a host as if each group were on a separate physical network. This feature of Hyper-V 3.0

is useful when hosting virtual machines of more than one organization, to prevent any

communication between machines that belong to different organizations.