Optimizing-QoS-vSphere_final

Traffic Shaping Enabled on a vDS.
QoS Best Practice 8: Limit Use of


When Needed
Before going into the details of how and
whentousetrafcshaping,itshould
be noted that this feature should be
used sparingly. It is a somewhat limited
way of using static bandwidth limits
andsegmentationtocontroltrafcon
aper-virtual-portbasis.Trafcshaping
on a per-port basis is very similar to the
use of other technologies that statically
segment 10GbE connections into multiple
connections that do not allow bandwidth
sharing when bandwidth is available.
This method was more useful in older
versions of ESX; with the release of 4.1
this approach is not as effective as using
trafc-typeQoScontrolsfoundinvSphere
4.1’sNetworkI/OControl.
Trafc-shapingpoliciescanbeestablished
foreachportgroupandeachdvPortor
dvPortgroup.ESXishapesoutbound
networktrafconvSwitchesandboth
inboundandoutboundtrafconavDS.
Trafcshapingrestrictsthenetwork
bandwidth available on a port, but it can
alsobeconguredtoallowburstsof
trafctoowthroughathigherspeeds.
Trafc-shapingpolicyusesthefollowing
parameters:
• establishes the
number of bits per second to allow
across a port, averaged over time: the
allowed average load.
• is the maximum
number of bits per second to allow
across a port when it is sending or
receiving a burst of traffic. This quantity
limits the bandwidth used by a port
whenever it is using its burst bonus.
Traffic Shaping Disabled on a vDS.
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