Figure 7.39 Dynamic Optimization options for a host group
While any host group can have the DO configurations set, the optimizations will be
applied only to hosts that are in a cluster. In addition, that cluster must support zero-
downtime VM migrations such as Live Migration on Hyper-V, XenMotion, and
vMotion on ESX. A manual DO can be initiated at any time by selecting a host cluster
and running the Optimize Hosts action, which will display a list of recommended
migrations. The great part is that this manual DO can be used even if DO is not
configured on the actual host group, allowing one-off optimizations to be performed.
PRO is still present in SCVMM 2012. It leverages Operations Manager and is used as a
more long-term placement technology, and it’s also the only extensible placement
technology. Third-party PRO packs can be installed to extend the placement logic.
Also shown in Figure 7.39 is an option to enable Power Optimization (PO, but I’m not
going to refer to it as that). While Dynamic Optimization tries to spread load across all
the hosts in a cluster evenly, Power Optimization aims to condense the number of
hosts that need to be running in a cluster in order to handle the virtual machine
workload without negatively affecting the performance of the virtual machines and
without powering down those not required. Consider a typical IT infrastructure that
during the workday is busy servicing employees and customers but during nonwork
hours is fairly idle. Power Optimization allows thresholds to be set to ensure that VMs
can be consolidated and that evacuated hosts can be powered down, provided the
remaining running hosts don’t have any CPU, memory, disk, or network resources
drop below the configured thresholds.
This is similar to the configuration options we set for DO, but this time it’s controlling