6.0.1

Table Of Contents
Cause
DRS never performs vMotion migrations when one or more of the following issues is present on the cluster.
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DRS is disabled on the cluster.
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The hosts do not have shared storage.
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The hosts in the cluster do not contain a vMotion network.
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DRS is manual and no one has approved the migration.
DRS seldom performs vMotion when one or more of the following issues is present on the cluster:
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Loads are unstable, or vMotion takes a long time, or both. A move is not appropriate.
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DRS seldom or never migrates virtual machines.
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DRS migration threshold is set too high.
DRS moves virtual machines for the following reasons:
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Evacuation of host that a user requested enter maintenance or standby mode.
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VM/Host DRS rules or VM/VM DRS rules.
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Reservation violations.
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Load imbalance.
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Power management.
Solution
Address the issues that are causing DRS to avoid performing vMotion migrations.
Host Problems
Host problems might cause DRS to not perform as expected.
DRS Recommends Host be Powered On to Increase Capacity When Total
Cluster Load Is Low
The host should be powered on to help provide more capacity for the cluster or help hosts that are
overloaded.
Problem
DRS recommends that the host be powered on to increase capacity when the total cluster load is low.
Cause
The recommendation might be made because:
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The cluster is a DRS-HA cluster. Additional powered-on hosts are needed in order to provide more
failover capability.
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Some hosts are overloaded and virtual machines on currently powered-on hosts can be moved to hosts
in standby mode to balance the load.
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The capacity is needed to meet the MinPoweredOn{Cpu|Memory}Capacity advanced options.
Solution
Power on the host.
vSphere Resource Management
130 VMware, Inc.