6.7

Table Of Contents
Figure 124. Red Cluster
cluster
Total Capacity: 12G
Reserved Capacity: 12G 15G
Available Capacity: 0G
RP1 (expandable)
Reservation: 4G
Reservation Used: 4G
Unreserved: 0G
RP2
Reservation: 2G
Reservation Used: 2G 5G
Unreserved: 0G
RP3 (expandable)
Reservation: 6G
Reservation Used: 2G
Unreserved: 4G 0G
VM1, 1G
VM7, 3G
VM2, 3G VM3, 1G VM4, 1G VM5, 1G VM6, 1G
Managing Power Resources
The vSphere Distributed Power Management (DPM) feature allows a DRS cluster to reduce its power
consumption by powering hosts on and off based on cluster resource utilization.
vSphere DPM monitors the cumulative demand of all virtual machines in the cluster for memory and CPU
resources and compares this to the total available resource capacity of all hosts in the cluster. If sufficient
excess capacity is found, vSphere DPM places one or more hosts in standby mode and powers them off
after migrating their virtual machines to other hosts. Conversely, when capacity is deemed to be
inadequate, DRS brings hosts out of standby mode (powers them on) and uses vMotion to migrate virtual
machines to them. When making these calculations, vSphere DPM considers not only current demand,
but it also honors any user-specified virtual machine resource reservations.
If you enable Forecasted Metrics when you create a DRS cluster, DPM will issue proposals in advance
depending on the rolling forecast window you select.
Note ESXi hosts cannot automatically be brought out of standby mode unless they are running in a
cluster managed by vCenter Server.
vSphere Resource Management
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