Hi! We have a Exchange 2007 environment with 4 cas/hub servers and 6 ccr clusters. We are planing to intrudce Exchange 2010 into the site with 2 multi role servers to start with. We will use our F5 to loadbalance our casarray. Now on to my question. When we start to move users to Ex2010, how will outlook know that they should use the new casarray and when a new client starts for the first time, how will it know that it should use the casarray and not any of the Exchange 2007 servers also listed in the SCP in AD? Regards, Martin

Hi Martin, The client will get the information from Autodiscover because all databases in the site where the CAS Array has been configured, will have that information set (RpcClientAccessServer) The RpcClientAccessServer attribute is used to tell Outlook clients during the profile creation process what server name should be in the profile. See: Demystifying the CAS Array Object - Part 1 http://blogs.technet.com/b/exchange/archive/2012/03/23/demystifying-the-cas-array-object-part-1.aspx Martina Miskovic

thanks Martina!! I have another question, we are aslo planning for installation exchange 2010 in another ad site. If i have mailbox in site A and travel to site b, when I log on with my pc and start outlook, I will be in another site. Will I still use the casarray in site a or will I use the casarray in site B?

Hi, It doesn't matter if you travel to a different site. You will always connect to the RpcClientAccessServer configured on the mailboxdatabase. So in other words, you would not connect to the casarray in Site B.Martina Miskovic

http://channel9.msdn.com/Events/TechEd/Europe/2010/UNC311 Great video. Basically, when Outlook opens, it finds all of necessary info in Active Directory and connects you. A more detailed description follows: Outlook queries AD for a Service Connection Point or SCPThe SCP points to the Autodiscover locationsOutlook connects to this locationAutodiscover returns the Exchange Web Service URLs the client needsIf there is more than one SCP found when Outlook goes searching, especially when there is a mixed 2007/2010 environment, basically the Autodiscover service on the 2007 CAS will issue a redirect to a CAS 2010 server or CAS Array. As I understand it, the CAS searches AD for your mailbox version, hence it knows where to tell Outlook to connect. If you look at a mailbox-enabled user in ADSIEdit, you will see a bunch of Exchange related information, such as homeMDB, homeMTA, msExchHomeServerName, etc. These are the values searched that return where the mailbox is actually located. I'm not sure if there is one particular attribute that is searched, but for sure it is in there.Outlook will then connect to the correct CAS and from there, will make a MAPI connection to the value of the RpcClientAccessServer setting on the database The clients will initially connect to the CAS closest to the actual computer. However, the URLs it gets in return will be for a CAS server closest to the mailbox itself. This is important if you have multiple sites with clients. MCITP Exchange 2010 | MCTS Exchange 2007 | MCITP Lync Server 2010 | MCTS Windows 2008 | MCSE 2003

cool, so If a user creates a outlook profile in site b and then after a year or so is relocated to site a, the mailbox will probably also be moved to to a mailbox server in site a. The outlook profile will change to the new value from the mailbox database in site a? sorry for all the questions but this is really confusing to me :)

Yes, the Outlook profile will change because it will connect to a different RpcClientAccessServer value which (if you have done things correctly), is configured when you create a CAS Array in each site.MCITP Exchange 2010 | MCTS Exchange 2007 | MCITP Lync Server 2010 | MCTS Windows 2008 | MCSE 2003

thank you so much both of you, a lot clearer now!! - Martin