MSExchange.org Monthly Newsletter of January 2008 Sponsored by: GFIWelcome to the MSExchange.org newsletter by Henrik Walther, Exchange MVP, MCA: Messaging (Exchange Ranger) Apprentice, MCTS/MCITP Exchange 2007, MCSE 2003 Messaging/Security. Each month we will bring you interesting and helpful information on Exchange Server. We want to know what all *you* are interested in hearing about. Please send your suggestions for future newsletter content to: henrik@msexchange.org 1. Explaining an Exchange 2007 CCR Deployment GothaWelcome to the January 2008 edition of the MSExchange.org newsletter! I hope all of you enjoyed your holidays and got a great start to 2008. This month I want to share a little Exchange Server 2007 Cluster Continuous Replication (CCR) gotcha I experienced during one of my Exchange Server 2007 messaging migrations. The specific issue I want to talk about arises if the messaging environment is split out over multiple Active Directory sites, and the Primary Domain Controller (PDC) FSMO role is located on a Domain Controller in a site other than the site in which you are deploying an Exchange Server 2007 RTM & SP1 Clustered Mailbox Server (CMS). If you try this or are planning to do so in the near future, you may very well get the following error message in the Exchange Server 2007 Setup Wizard or command line: Clustered Mailbox Server ......................... FAILED The computer account 'excluster' was created on the domain controller '\\dc01.domain.local', but has not replicated to the desired domain controller (dc01.domain.local) after waiting approximately 60 seconds. Please wait for the account to replicate and re-run setup /newcms. If you then wait for the replication to finish and run setup again, you receive an error message similar to the following: Clustered Mailbox Server Performing Microsoft Exchange Server Prerequisite Check Configuring Microsoft Exchange Server Clustered Mailbox Server ......................... FAILED Cannot calculate value of property "AdminDisplayVersion": "SerialNumber property is not present.". The Exchange Server Setup operation did not complete. For more information, visit http://support.microsoft.com and enter the Error ID. Exchange Server setup encountered an error. So what is happening here? Well as mentioned this error only occurs if the PDC FSMO role is out of site, that is the PDC FSMO role is located on a Domain Controller in another site that the site where you deploy the CCR cluster, Exchange setup will fail. This is not an Exchange 2007 RTM issue; it even occurs with Exchange Server 2007 SP1! Some of you might think that the issue can be resolved by specifying which domain controller to use when running Exchange Server 2007 Setup (with the DomainController flag), but unfortunately this method does not resolve the issue. The reason why this is so is because the Windows Server 2003 Microsoft Cluster Service (MSCS) always creates the computer account objects on the Domain Controller holding the PDC FSMO role, even when it is located on another AD site. This can result in that the computer account object does not replicate to the local site in time for Exchange 2007 Setup to complete. So why does this issue occur and most importantly, how can I fix it? Other than moving the PDC FSMO role to the local AD site (which is not an option for most of the Corporate Enterprise customers out there), another workaround also exists. Using the Cluster Administrator (CluAdmin.msc), you can remove the CMS resource that was created during the failed Exchange setup, and then create the CMS computer account object manually and wait for it to replicate to the local AD site (remember than you need the cluster service account (CSA) full control to the new object). When you have created the object manually you simply re-run Exchange Setup and complete the installation as normal. I want to thank Tim McMichael who is a Support Professional in the Enterprise Messaging group at Microsoft for the support he provided when I initially experienced this issue. Also, thank you to Ayla Kol from the Exchange Product Group for explaining this issue further. Cheers, Note: 2. Order Henrik Walther's Exchange Server 2007 book
3. MSExchange.org Learning Zone Articles of InterestWe have a great group of articles in the Learning Zone that will help you get a handle on your most difficult configuration issues. Here are just a few of the newer and more interesting articles:
4. KB Articles of the MonthHere are some interesting and useful MSExchange related articles posted by Microsoft in the last month: Exchange Server 2007
Exchange Server 2003
5. Exchange WebcastsJanuary 2008 TechNet Webcast: Exchange Server 2007 in Depth (Part 1 of 8): Overview (Level 200) TechNet Webcast: Exchange Server 2007 in Depth (Part 2 of 8): Deployment and Migration (Level 200) TechNet Webcast: Exchange Server 2007 in Depth (Part 3 of 8): Introduction to the New Management Console (Level 200) TechNet Webcast: Exchange Server 2007 in Depth (Part 4 of 8): Introduction to Windows PowerShell Scripting (Level 200) TechNet Webcast: Exchange Server 2007 in Depth (Part 6 of 8): Disaster Recovery (Level 200) February 2008 TechNet Webcast: Exchange Server 2007 in Depth (Part 7 of 8): Key Scenarios, Examples, Demos, and How-to's (Level 300) TechNet Webcast: Exchange Server In Depth (Part 8 of 8): Master Concepts and Optimize Your Server Environment (Level 300) Momentum Webcast: Simplifying Collaboration and Communication Using Microsoft Office, Exchange Server, and Communications Server (Level 100) 6. MSExchange News of the Month
7. Ask Henrik Walther a questionQUESTION: I plan to use CCR with 2 mailbox servers and also run CAS/HUB in NLB. During my research, I have a couple of questions. In this model, where should I locate the File Share Witness? What happens if the File Share Witness is a single point of failure and the server it resides on crashes? ANSWER: You should still place the file share witness on a Hub Transport server in the same AD site as the clustered mailbox servers, but please bear in mind that it is best practice to point the failover cluster to the file share witness using a CNAME record, as this makes it so much easier to change the witness should the Hub Transport server crash etc. You can see how this is accomplished here: http://technet.microsoft.com/en-us/library/bb124922.aspx TechGenix Sites
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