Hi,

This is an interesting article to be aware of when you are doing virtualization with Exchange. Particularly I want to point out the following section which is of interest if you’re considering HA for Exchange…

Choosing a High Availability Solution for a Virtualized Exchange Server

We recommend using the built-in Exchange Server high availability solutions for virtualized Exchange servers instead of hypervisor-provided clustering or portability solutions (such as Hyper-V's quick migration feature). The features found in Exchange Server (in particular, cluster continuous replication (CCR)) provide greater benefits than those found in hypervisor solutions that move virtual machines between physical root machines.

The built-in data replication mechanism in Exchange (continuous replication) can be combined with Windows failover clustering in a configuration known as CCR. CCR can be deployed in a hardware virtualization environment, thereby providing you with a service and data availability solution for Exchange 2007 in a virtualized environment. In a virtualized CCR (or SCC) environment, each guest machine that is a node in the cluster must be hosted on separate physical root machines to provide true redundancy and high availability.

Note:

It is supported to deploy CCR or SCC using a combination of physical nodes and virtual nodes. As with all Exchange high availability configurations, you must ensure that all nodes are sized appropriately to handle the full workload during scheduled or unscheduled outages.

We do not recommend using hypervisor-based virtual machine migration (such as Hyper-V's quick migration) for virtualized Exchange servers. In a virtual machine migration configuration, an unscheduled outage can result in data loss. In a CCR environment, this type of data loss is largely mitigated by a feature called transport dumpster. The transport dumpster takes advantage of the redundancy in the environment to reclaim some of the data affected by the failover

Virtual machine migration vs. cluster continuous replication

For more info read http://technet.microsoft.com/en-us/library/cc794548.aspx

Sincerely,

Tonino Bruno | ICT Consultant | www.proexchange.be