Physical Cluster of Hyper-V for Exchange 2013 RRS feed

  • Question

  • Hi!

    Can anybody explain what is the best fault tolerant and Load Balancing Solution for Exchange 2013 and what is the purpose of and difference between a Physical Hyper-V cluster and Exchange DAG?


    Thursday, May 30, 2013 11:32 AM

All replies

  • Hi there,

    A hypervisor providing fault tolerance for a single VM is only good to protect against hardware failure. for example storage fails, or a compute node fails. The Hypervisor will then bring the virtual machine back up on other redundant hardware within the high availability configuration of the Hypervisor in use.

    If you have a single Exchange box, this protects it against hardware failure. What it doesnt' protect it against is issues with Server Applications on the OS, or the actual OS itself.

    A DAG will create multiple copies of mailbox data, protecting against that logical corruption, so if an issue occurs within the OS or the Server application, failover can occur to a known good working DAG member and availability can continue.

    This is a very high level answer to your high level question.

    Read up on Exchange DAG availability here:

    HyperV availability here:

    Both articles are not recent, but should give you the insight to the level of understanding you need.


    Oliver Moazzezi | Exchange MVP, MCSA:M, MCITP:Exchange 2010,MCITP:Exchange 2013, BA (Hons) Anim | | |

    Tuesday, June 4, 2013 10:33 AM