Exchange Server 2019 Architecture and new features

With Exchange Server 2019 around, it is essential to explore the architecture of the same. Architecture of Exchange server 2019 is same as that of Exchange server 2016. It revolves around two server roles as below.

• Mailbox Server
• Edge Transport Server

Mailbox Server role

The Mailbox Server role is installed in the Active Directory site where at least one writeable domain controller is deployed which is also a global catalog server.

What is Global Catalog Server?

The global catalog is a feature of Active Directory domain controllers that allows for a domain controller to provide information on any object in the forest, regardless of whether the object is a member of the domain controller’s domain.

Mailbox server includes three major components as listed below.

• Mailbox Databases
• Transport services and
• Client Access Services

Unified messaging (UM) functionality which existed in previous versions of Exchange Server has been deprecated in this release. Since UM functionality no longer available, Customers can choose to transition to Skype for Business Cloud Voice Mail as alternative,.

To know about Mailbox Server role and its components in detail, do check my other post on Mailbox server 2019.

Edge Transport role

Edge transport role is designed to run in perimeter network that reduces the surface attack area. The Edge Transport role is an optional Exchange Server role as we can also use the Exchange Online Protection (EOP) as cloud based filtering service or any third party validated filtering solution as an alternative to it. When deployed, Edge transport role handles all external mail flow for the Exchange organisation and provides anti-spam protection for Exchange organisation.

New features in Exchange Server 2019

• Exchange now supports up to 256 GB memory and 48 CPU cores.
• Exchange Server 2019 can be installed on Windows Server Core 2019 for more secure configuration as it minimises the surface attack area and runs fewer but required components on the server.
• Client Access Rules to increase security when managing Exchange environment and only allow administration of Exchange from the internal network.
• In addition to the currently recommended JBOD drives, it now works on storage that’s a combination of SSD drives.
• The information store process now uses dynamic memory cache allocation due to which memory is optimised for active database usage.
• The search infrastructure that has been completely rebuilt for cloud scale and reliability in Exchange Online is also available in Exchange 2019 on-prem. This allows for large files indexing and better search performance.
• The changes to the search architecture result in significantly faster and more reliable failover over between servers.