I have a single domain ex. company.com that is separated into 2 Active Directory sites. Each site has a Exchange 2010 server hosting CAS, Mailbox, and Hub Roles. I want to have OWA access Externally via https://mail.company.com. How do I do this as each user would have to log into their AD Site Exchange Server where their mailbox is located. Does that mean I would have to have two external DNS addresses setup for OWA. Example https://mail1.company.com (pointing to exchange server in AD site 1) and https://mail2.company.com (pointing to exchange server in AD site 2).

If you want both AD sites to have internet facing OWA (and other Exchange services) then you will need to utilize two different namespaces for OWA. A user can log into either one, and then will be redirected to the proper server if their mailbox is in the other site. Note that the redirection is not completely seamless, they will be presented with the other link that they will need to click and sign in again. The other option is to set up proxying where it is seamless to the user and only will require one external namespace. This might not be a good option on your depending on your WAN. Here is more info: http://technet.microsoft.com/en-us/library/bb310763.aspx Tim Harrington - Catapult Systems - http://HowDoUC.blogspot.com

You might want to consider a splash page- accessbile at http://mail.company.com From there users can click on a link corresponding with their region.

You have to configure internal proxying for both servers in both Active Directory sites, because OWA and ECP publish their internal URLs in the same AD site! You have to use Kerberos authentication for the CAS server roles to identify eachother in different AD sites at OWA level. The easiest way to acomplish this is to set your OWA Virtual Directory for Windows based authentication. You can use one external name published at your primary site, and internal proxying will reroute the users to the secondary AD site. Keep the external URL blank in the secondary site, to acheive the required goal. NOTE: This solution is valid if you have Edge Transport Role installed in your Primary site only. If there is an Edge Transport Role in secondary site as well, you have to publish two seperate URLs, and the users will be redirected to the second link by default internal proxying. You have to use Windows Authenticaion instead of Forms based authentication anyway! Best of luck!

Hi Hogarts, Any update for your issue? Above gave some good suggestion. If you still have any question, please tell us. Regards! Gavin Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

how to configure proxying .i have 2 sites in the first site i have only one client access server facing the internet which handle the OWA and in the second site i have client access server,mailbox server and hub transport server. i need that the client access server provide the outlook web access. how can i do this?