6.0.1

Table Of Contents
No Hosts are Powered Off When Total Cluster Load is Low
Hosts are not powered off when the total cluster load is low.
Problem
Hosts are not powered off when the total cluster load is low because extra capacity is needed for HA
failover reservations.
Cause
Hosts might not be powered off for the following reasons:
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The MinPoweredOn{Cpu|Memory}Capacity advanced options settings need to be met.
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Virtual machines cannot be consolidated onto fewer hosts due to their resource reservations, VM/Host
DRS rules, VM/VM DRS rules, not being DRS-enabled, or not being compatible with the hosts having
available capacity.
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Loads are unstable.
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DRS migration threshold is at the highest setting and only allows mandatory moves.
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vMotion is unable to run because it is not configured.
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DPM is disabled on the hosts that might be powered off.
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Hosts are not compatible for virtual machines to be moved to another host.
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Host does not have Wake On LAN, IPMI, or iLO technology. Either one is required for DPM to enter a
host in standby.
Solution
Address the issue that prevents hosts from being powered off when the total cluster load is low.
Hosts are Powered Off When Total Cluster Load is High
Hosts are powered off when total cluster load is high.
Problem
DRS determined that virtual machines could be run on a fewer number of hosts without degrading the host
or virtual machine performance. DRS is also constrained from moving the virtual machines running on the
highly-utilized hosts to the hosts scheduled for power-off.
Cause
This occurs when the total cluster load is too high.
Solution
Reduce the cluster load.
DRS Seldom or Never Performs vMotion Migrations
DRS seldom or never performs vMotion migrations.
Problem
DRS does not perform vMotion migrations.
Chapter 17 DRS Troubleshooting Information
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