Configuring Exchange Server 2010 DAG

Microsoft Professional Advisory Services is a support option that provides short-term, proactive, consultative support beyond break-fix product maintenance needs. This includes working with the same technician for assistance with issues like product migration, code review, or new program development and is a remote, phone-based support option. This service is typically used for shorter engagements, and is designed for developers and IT professionals who do not require the traditional onsite consulting or sustained account management services that are available from other Microsoft support options.

For additional information on Microsoft Advisory Services, including on how to engage, refer to this Microsoft web page:

http://support.microsoft.com/gp/AdvisoryService (http://support.microsoft.com/gp/AdvisoryService)

Assists customers with setup of Exchange Server 2010 Database Availability Group(s) (DAG).The purpose of this document is to assist the Pro-Advisory Support Engineer in scoping a case in which a customer is planning to deploy Exchange Server 2010 Database Availability Group(s) (DAG).

Configuration will involve the following phases:  Planning, Deployment, and Finalizing.

• Planning: understanding the environment and suggesting the requirements for high availability.
• Deployment: setup of the DAG and adding the member node.
• Finalization: test if the DAG is successfully running.

This document will help in better understanding the environment and defining the course of action.

Assumptions

• The current Exchange Server environment is configured properly per the Exchange Pre-Deployment Analyzer (http://www.microsoft.com/downloads/details.aspx?FamilyID=88b304e7-9912-4cb0-8ead-7479dab1abf2&displaylang=en) (ExPDA), and is healthy as determined by a full Exchange Best Practice Analyzer (ExBPA) health check and is ready for deploying Exchange Server 2010. If this is the first Exchange Server 2010 deployment then it is assumed that all the pre-requisite are taken care as determined by the Exchange 2010 Deployment Assistant (http://technet.microsoft.com/en-us/library/ee681665.aspx) .
• The server environment meets the requirement as per the Planning for Exchange 2010 (http://technet.microsoft.com/en-us/library/aa995902.aspx) TechNet article. Any other issues need to be resolved via separate break/fix incidents. It is highly recommended that the customer perform the ExBPA health check and resolve any issues prior to beginning work on the advisory case scope. If any unexpected break/fix issues arise while working on the scoped issue, a maximum of thirty (30) minutes will be spent troubleshooting the other issues. This will be billed to the current advisory case. If the issue is not resolved in thirty (30) minutes the customer must open a new break/fix support case, at additional cost, to address the problem.  The Professional Advisory Support Engineer may work that break/fix support case at their discretion.
• The current environment meets all prerequisites for installing Exchange Server 2010 as per the Exchange 2010 Prerequisites (http://technet.microsoft.com/en-us/library/bb691354.aspx) TechNet article. This includes all Active Directory & DNS configuration requirements as per the Planning Active Directory (http://technet.microsoft.com/en-us/library/bb123715.aspx) TechNet article.
• The scenarios where disjoint namespace are supported for Exchange Server 2010 are as per the Understanding Disjoint Namespace Scenarios (http://technet.microsoft.com/en-us/library/bb676377.aspx) TechNet article.
• The storage architecture and configuration should be as per these TechNet articles: Understanding Storage Configuration (http://technet.microsoft.com/en-us/library/ee832792.aspx) , Mailbox Server Processor Capacity Planning (http://technet.microsoft.com/en-us/library/ee712771.aspx) , Exchange 2010 Mailbox Server Role Requirements Calculator (http://msexchangeteam.com/archive/2009/11/09/453117.aspx) and Updates to the Exchange 2010 Mailbox Server Role Requirements Calculator (http://msexchangeteam.com/archive/2010/01/22/453859.aspx) .

Scoping Questions

1. Topology documentation:

• How many AD sites, domains, and DC/GC’s are present in the environment (list names)?
• How the AD sites are connected (network topology) (list names)?
• Are any servers in a perimeter network (DMZ)?  Note: Exchange Server 2010 does not support CAS, HUB or MBX server roles in a perimeter network.  The only server role supported in a perimeter network is the EDGE role.
• How is the storage architecture designed?

2. How do you want to configure DAG?  Refer to these TechNet articles:

• Installation Guide Template - DAG Member (http://technet.microsoft.com/en-us/library/ff622321.aspx)
• High Availability and Site Resilience (http://technet.microsoft.com/en-us/library/dd638121.aspx) Note: DAG with Site Resilience configurations are not covered under Professional Advisory support scenarios.
• Database Availability Group Design Examples (http://technet.microsoft.com/en-us/library/dd979781.aspx)
  
  o   Two-member DAG in single datacenter/Active Directory site - Both members are in the same datacenter.
  
  o   Four-member DAG in a single datacenter/Active Directory site - All four-members are in the same datacenter.
  
  o   Four-member DAG in two datacenters/Active Directory sites - Two members in the primary datacenter and two in the second datacenter.

Guidance Questions

There are many different design dimensions that have to be considered when designing for high availability with Exchange Server 2010. Due to these new sizing factors, additional steps are required to size mailbox servers when configured for Mailbox Resiliency.

• The locality of the users will ultimately determine the DAG architecture
  
  a.       Are users primarily located in one datacenter?
  
  b.      Are users located in multiple datacenters?
  
  c.       Is there a requirement to maintain user population in a particular datacenter?
  
• What kind of a solution are you looking for?
  
  a.       Mailbox Resiliency or stand alone? 
  
  b.      Site resiliency?
  
• Database Availability Group design
  
  a.       How many DAGs should I deploy?
  
  b.      How many members should be in a DAG?
  
  c.       How many database copies you plan to activate on a per server basis when configured for Mailbox Resiliency?
  
  d.      What types of database copies do you want to deploy? HA database copies or Lagged database copies.

You can use the information in the Mailbox Server Processor Capacity Planning (http://technet.microsoft.com/en-us/library/ee712771.aspx) TechNet article to better understand the design guidance for sizing mailbox servers when configured for mailbox resiliency.

DAG design examples are listed in the Database Availability Group Design Examples (http://technet.microsoft.com/en-us/library/dd979781.aspx) TechNet article and here:

• Two-member DAG in single datacenter/Active Directory site - Both members are in the same datacenter.
• Four-member DAG in a single datacenter/Active Directory site - All four-members are in the same datacenter.
• Four-member DAG in two datacenters/Active Directory sites - Two members in the primary datacenter and two in the second datacenter.

Note: DAG with Site Resilience configurations are not covered under Professional Advisory support scenarios.

Below is a list of self-help resources or this scenario. These resources may also be used by Microsoft Support Engineers during an Advisory Services engagement.

Planning

Understanding Database Availability Groups (http://technet.microsoft.com/en-us/library/dd979799.aspx)

High Availability in Exchange Server 2010 (http://msexchangeteam.com/archive/2009/06/14/451609.aspx)

Database Availability Group Design Examples (http://technet.microsoft.com/en-us/library/dd979781.aspx)

Understanding Active Manager (http://technet.microsoft.com/en-us/library/dd776123.aspx)

Understanding Mailbox Database Copies (http://technet.microsoft.com/en-us/library/dd979802.aspx)

Mailbox Server Storage Design (http://technet.microsoft.com/en-us/library/dd346703.aspx)

Planning for High Availability and Site Resilience (http://technet.microsoft.com/en-us/library/dd638104.aspx)

Understanding Datacenter Activation Coordination Mode (http://technet.microsoft.com/en-us/library/dd979790.aspx)


Deployment

Create a Database Availability Group (http://technet.microsoft.com/en-us/library/dd638129.aspx)

Manage Database Availability Group Membership (http://technet.microsoft.com/en-us/library/dd351278.aspx)

Configure Database Availability Group Properties (http://technet.microsoft.com/en-us/library/dd297985.aspx)

Understanding Datacenter Activation Coordination Mode (http://technet.microsoft.com/en-us/library/dd979790.aspx)

Configure Database Availability Group Network Properties (http://technet.microsoft.com/en-us/library/dd297927.aspx)

Add a Mailbox Database Copy (http://technet.microsoft.com/en-us/library/dd298080.aspx)

Deploying High Availability and Site Resilience (http://technet.microsoft.com/en-us/library/dd638129.aspx)


Finalization

Managing Database Availability Groups (http://technet.microsoft.com/en-us/library/dd298065.aspx)

Monitoring High Availability and Site Resilience (http://technet.microsoft.com/en-us/library/dd351258.aspx)

Monitoring Exchange 2010 (http://technet.microsoft.com/en-us/library/ee332313.aspx)

Switchovers and Failovers (http://technet.microsoft.com/en-us/library/dd298067.aspx)

Activate a Mailbox Database Copy (http://technet.microsoft.com/en-us/library/dd298067.aspx)

Perform a Server Switchover (http://technet.microsoft.com/en-us/library/dd298187.aspx)

Installing Update Rollups on Database Availability Group Members (http://technet.microsoft.com/en-us/library/ee861125.aspx)

Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice. See Terms of Use (http://go.microsoft.com/fwlink/?LinkId=151500) for other considerations.