Specifications

Best Practices for Virtualizing and Managing Exchange 2013
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Dynamic Optimization
Once Exchange 2013 virtual machines have been deployed onto the Hyper-V cluster, VMM actively
monitors key cluster and host metrics—such as CPU, Memory, Disk, and Network—to see if it can better
balance the virtual machine workloads across different hosts (Figure 42). For example, you may have a
number of hosts in a cluster, and one of the hosts has some Exchange 2013 virtual machines that are
exhibiting higher levels of demand than some others on other hosts. VMM can recognize this, and
automatically live migrate, with no downtime, some of the other virtual machines on that busy host to
less-busy hosts, freeing up valuable resources. This helps to ensure that workloads such as Exchange
2013, inside the virtual machines always receive the resources they need to meet demand, without
impacting other workloads running on the cluster.
Figure 42: System Center 2012 SP1 Virtual Machine Manager – Dynamic Optimization
Best Practices and Recommendations
Dynamic Optimization can be configured on a host group to migrate virtual machines within host
clusters with a specified frequency and aggressiveness. Aggressiveness determines the amount of
load imbalance that is required to initiate a migration during Dynamic Optimization. By default,
virtual machines are migrated every 10 minutes with medium aggressiveness. When configuring
frequency and aggressiveness for Dynamic Optimization, you should factor in the resource cost of
additional migrations against the advantages of balancing load among hosts in a host cluster. By
default, a host group inherits Dynamic Optimization settings from its parent host group.