Guys If i setup one site and exchange 2010 do i need the CAS role if mail flow will only be internal. No site-to-site and no site-to-external?

If i setup one site and exchange 2010 do i need the CAS role if mail flow will only be internal. No site-to-site and no site-to-external? CAS is not used for mail flow. If you talking for HUB server yes it is needed for even internal mailflow. For that matter to email yourself as well you need HUB.Jasjit Singh Dhindsa | ITIL v3 | IASA Foundation Certified | MCITP:EMA Exchange 2010/2007 | MCTS:OCS 2007 | Exchange 2010/2007 | MCSA:Messaging/Security | MCSE:Messaging/Security

Thanks for your respone. Even if i e-mail someone else in the same site but on a different MB Server i do NOt need a CAS hey?

Even if i e-mail someone else in the same site but on a different MB Server i do NOt need a CAS hey? Yes You still need a HUB server. Even if its on diffrent MB server in same AD Site.Jasjit Singh Dhindsa | ITIL v3 | IASA Foundation Certified | MCITP:EMA Exchange 2010/2007 | MCTS:OCS 2007 | Exchange 2010/2007 | MCSA:Messaging/Security | MCSE:Messaging/Security

Hi I'm NOT talking about a HUB T server but a CAS server. I know one need a HT server for mailflow. I do not need a CAS Server to e-mail from one user to another in the same site hey? Can i send from one site to another without a CAS or do i need one then?

I do not need a CAS Server to e-mail from one user to another in the same site hey? Without CAS Server you cannot log into your Mailbox. No you do not need CAS Server for Sending E-Mail but you need it for connecting to your mailbox. Can i send from one site to another without a CAS or do i need one then? You can send email from one user to other user in other server without CAS server but you need HUB server in both the sites to deliver e-mail. More over you need CAS server in both the sites to log into the user mailbox.Jasjit Singh Dhindsa | ITIL v3 | IASA Foundation Certified | MCITP:EMA Exchange 2010/2007 | MCTS:OCS 2007 | Exchange 2010/2007 | MCSA:Messaging/Security | MCSE:Messaging/Security

Thank Jasjit Yes, i did a quick lab and that is what i discovered. You cannot open your mailbox without a CAS but you can send mail which in my opinion is abit stupid because now someone would need a extra server in a site just to open a mailbox :<

I total Agree...But do we have choice :(Jasjit Singh Dhindsa | ITIL v3 | IASA Foundation Certified | MCITP:EMA Exchange 2010/2007 | MCTS:OCS 2007 | Exchange 2010/2007 | MCSA:Messaging/Security | MCSE:Messaging/Security

Thank you for your time. I have marked as answersed and voted your replies as helpfull

On Thu, 3 Nov 2011 10:15:44 +0000, CraMey wrote: >If i setup one site and exchange 2010 do i need the CAS role if mail flow will only be internal. No site-to-site and no site-to-external? Yes, you do. Exchange 2010 uses CAS as the connection point for all clients -- including Outlook. --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

On Thu, 3 Nov 2011 11:08:35 +0000, CraMey wrote: >Yes, i did a quick lab and that is what i discovered. You cannot open your mailbox without a CAS but you can send mail which in my opinion is abit stupid because now someone would need a extra server in a site just to open a mailbox :< You don't need any other servers, just an additional role. --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

Thanks you Rich for your response. I now understand the concept

By the way, as far as I know, you can assign CAS and HUB and Mailbox Exchange Server roles to the very same physical maschine :)

Hi Jasjit, I do not need a CAS Server to e-mail from one user to another in the same site hey? Without CAS Server you cannot log into your Mailbox. No you do not need CAS Server for Sending E-Mail but you need it for connecting to your mailbox. CAS Server is requird to send email The purpose of RPC client access service is to act as an endpoint. The mail flow for internal MAPI communication also needs CAS. The mail flow is Mailbox submission Service in Mbx - the storedriver in hubtransport - Categorizer - MAPI RPC (CAS) - The RPC Client Access service provides data access through a single, common path of the Client Access server http://technet.microsoft.com/en-us/library/ee332317.aspx