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Table Of Contents
Table 111. Allocation Parameters for System Trac
Parameter for Bandwidth Allocation Description
Shares Shares, from 1 to 100, reflect the relative priority of a system
traffic type against the other system traffic types that are active
on the same physical adapter.
The amount of bandwidth available to a system traffic type is
determined by its relative shares and by the amount of data that
the other system features are transmitting.
Reservation The minimum bandwidth, in Mbps, that must be guaranteed on a
single physical adapter. The total bandwidth reserved among all
system traffic types cannot exceed 75 percent of the bandwidth
that the physical network adapter with the lowest capacity can
provide.
Reserved bandwidth that is unused becomes available to other
types of system traffic. However, Network I/O Control does not
redistribute the capacity that system traffic does not use to
virtual machine placement.
Limit The maximum bandwidth, in Mbps or Gbps, that a system traffic
type can consume on a single physical adapter.
Example Bandwidth Reservation for System Trac
The capacity of the physical adapters determines the bandwidth that you guarantee. According to this
capacity, you can guarantee minimum bandwidth to a system feature for its optimal operation.
For example, on a distributed switch that is connected to ESXi hosts with 10 GbE network adapters, you
might configure reservation to guarantee 1 Gbps for management through vCenter Server, 1 Gbps for
vSphere Fault Tolerance, 1 Gbps for vSphere vMotion traffic, and 0.5 Gbps for virtual machine traffic.
Network I/O Control allocates the requested bandwidth on each physical network adapter. You can
reserve no more than 75 percent of the bandwidth of a physical network adapter, that is, no more than 7.5
Gbps.
You might leave more capacity unreserved to let the host allocate bandwidth dynamically according to
shares, limits, and use, and to reserve only bandwidth that is enough for the operation of a system
feature.
Configure Bandwidth Allocation for System Trac
Assign bandwidth for host management, virtual machines, NFS storage, vSphere vMotion, vSphere Fault
Tolerance, vSAN, and vSphere Replication on the physical adapters that are connected to a vSphere
Distributed Switch.
To enable bandwidth allocation for virtual machines by using Network I/O Control, configure the virtual
machine system traffic. The bandwidth reservation for virtual machine traffic is also used in admission
control. When you power on a virtual machine, admission control verifies that enough bandwidth is
available.
vSphere Networking
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