Mastering Windows Server 2016 Hyper-V

In addition to providing the drivers and components required for the most optimal
utilization of resources between the guest and the hypervisor, other integration
services exist, as described in the following list. Note that each service can be disabled
if required through the settings of the virtual machine in the Management ➣
Integration Services section. Unless there is a specific reason not to, you should leave
Integration Services enabled.

Operating   System  Shutdown    Enables the guest   operating   system  to  be  cleanly

shut    down    from    the Hyper-V manager or  the management  interfaces  that    Hyper-V

provides,   such    as  PowerShell  and WMI.

Time    Synchronization Keeps   the time    of  the guest   OS  synchronized    with    the

host    operating   system.

Data    Exchange    Allows  the exchange    of  specific    Registry    location    values  between

a   guest   and the parent  partition,  known   as  key-value   pairs.  The Hyper-V host

writes  to  location    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Virtual

Machine\Guest\Parameters    within  the VM, and the OS  in  the guest   can then    read

from    this    location    to  gather  information about   the host.   This    information includes

the Hyper-V hostname    (which  is  the cluster name    if  it’s    a   cluster node),  version

information,    its fully   qualified   name,   and the actual  VM’s    name    and ID, as  shown

in  Figure  5.32.   This    can easily  be  read    using   PowerShell. For example,    within  a

virtual machine,    to  find    which   Hyper-V host    it  is  on, I   use the following   PowerShell

command:

$regPath    =   "HKLM:\SOFTWARE\Microsoft\Virtual   Machine\Guest\Parameters"

(Get-ItemProperty   -Path   $regPath).HostName

Figure 5.32 Registry within a virtual machine showing information about the host

Conversely, the Hyper-V host reads information from
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Virtual Machine\Auto in the guest, which
is populated by the guest OS, giving Hyper-V a lot of information about the OS,
including version, naming, and IP configuration. This type of information exchange
can be useful for many types of management operations, automation, and inventory.
The complete list of values can be found at the following location, which documents
the Msvm_KvpExchangeDataItem class: