Exchange Server Preferred Architecture

First look at Exchange Server 2016 and what's new for admins

Finally Exchange Server 2016 on the way

Finally Microsoft introduce Exchange Server 2016, there is a single building block that provides the client access services and the high availability architecture.

 

                                                   

This architecture is designed to enable you to have fewer physical Exchange servers in your environment. Fewer physical servers mean lower costs for a variety of reasons:

• Operational costs are almost always higher than the capital costs. It costs more to manage a server over its lifetime than it does to purchase it.
• You purchase fewer Exchange server licenses. This architecture only requires a license for one Exchange server and one operating system, while breaking out the roles required multiple Exchange server licenses and multiple operating system licenses.
• Deploying fewer servers has a trickle-down effect across the rest of the infrastructure. For example, deploying fewer physical servers may reduce the total rack and floor space required for the Exchange infrastructure, which in turn reduces power and cooling costs.

This architecture ultimately distributes the load across a greater number of servers than deploying single-role servers because all Mailbox servers also handle client access because:

• You’re distributing the load across a greater number of physical machines, which increases scalability. During a failure event, the load on the remaining servers only increases incrementally, which ensures the other functions the server is performing aren’t adversely affected.
• The solution can survive a greater number of Client Access role (or service) failures and still provide service, which increases resiliency.

• Removed the Client Access Server role (communication between servers still occurs at the protocol layer)
• Added the Client Access services to the Mailbox role
• No Client Connect directly to back-end
• No IP Address require for DatabaseAvailabilityGroupIpAddresses
• Replay lag manager default no manual task
• Database fail-over times reduced 33% compare to 2013.
• Still we can use Edge Server 2013

The load balancer configuration is also not affected by this architectural change:

• A Client resolves the namespace to a load balancer virtual IP and assigns the session to a mailbox server in load balanced pool.
• The Mailbox server authenticates the request and performs a service discovery by accessing Active Directory to retrieve the mailbox version and location information (Database etc.)
• Proxy and redirection decision make by Mailbox server.
• Mailbox server queries an Active Manager instance to determine the which server hosting the Active Copy and proxy the request to the Mailbox server.
• Mailbox server will redirect the request to the Mailbox server hosting the active copy of the user’s database, as the telephony devices support redirection and need to establish their SIP and RTP sessions    directly with the Unified Messaging services on the Mailbox server
• Reduced bandwidth requirements between the active copy and a passive copy by 40% replicated with each database copy.
• Search has been improved such as  length of time to return search results, especially in online mode clients like OWA
• Improve the Document Collaboration
• Improve on Extensibility mainly Office 365
• Exchange Server 2016 does not support connectivity via the MAPI/CDO library.
• Easy Coexistence with Exchange Server 2013

References : http://blogs.technet.com/b/exchange/archive/2015/05/05/exchange-server-2016-architecture.aspx