Mastering Windows Server 2016 Hyper-V

cluster cannot  use this    network.    This    would   be  configured  on  something   like    an

iSCSI   network,    which   is  automatically   set if  the iSCSI   Software    Initiator   is  bound

to  the IP  address.

These roles can also be configured by using this PowerShell command:

(Get-ClusterNetwork "").Role=

These three settings are used by clustering to create an automatic metric for each
network adapter, which sets the priority for the preferred network to be used for
cluster communications from all those available. You can see the metrics by using the
following PowerShell:

PS C:> Get‐ClusterNetwork | ft Name, Role, AutoMetric, Metric ‐AutoSize
Name Role AutoMetric Metric
—— ——————————
Cluster Network 1 True 30240
MGMT Network 3 True 70384

The lower the metric value, the cheaper it is considered to be and therefore a greater
preference to be used for cluster communications. The way these values are calculated
is primarily on the role of the cluster, which sets a starting value for the metric:

Role    of  1:  Starting    metric  40000

Role    of  3:  Starting    metric  of  80000

Then the metric is reduced for each NIC, based on its link speed and whether it’s
RDMA capable and has RSS capabilities. The higher the performance and feature set
of the NIC, the greater the metric reduction, making it cheaper and therefore more
appealing to be used for cluster communications. It is possible to change these metric
values by disabling AutoMetric on the cluster network and then manually setting a
metric value, but generally this should not be performed. Note that this prioritization
of networks for cluster communications does not apply to SMB-based
communications; SMB uses its own selection mechanism. If you did need to modify
the metric, use the following:

(Get-ClusterNetwork "".AutoMetric = $false
(Get-ClusterNetwork "".Metric = 42

When considering network capacity planning for network traffic, it’s important to
realize that in addition to network health monitoring (heartbeats) traffic, the cluster
network is used for intra-cluster communications such as cluster database updates
and CSV I/O redirection.

The heartbeat communications are lightweight (134 bytes, to be exact) in Windows
Server 2012 R2 and Windows Server 2016, and they are sent by default once a second.
You don’t require a big network pipe (that is, bandwidth), but the heartbeats are
sensitive to latency (the lag between a request and response), because if too many
heartbeats are not acknowledged in a period of time, the host is considered