Applies to: Exchange Server 2010 SP2
Topic Last Modified: 2011-07-29
When configuring a hybrid deployment, it's necessary to configure a hybrid server in your existing Exchange organization. The hybrid server is an existing physical server configured with Exchange 2010 server roles that coordinates communication between your existing Exchange organization and the cloud-based organization. This communication includes message transport and messaging features between the on-premises and cloud-based organizations.
Hybrid Server Roles
The hybrid server requires the following Exchange 2010 server roles to be installed:
- Client Access server role The Client
Access server role on the hybrid server provides essentially the
same functionality provided by other Client Access servers in your
Exchange organization with a few additions required to support a
hybrid deployment. All client connectivity for the hybrid
organization, including Outlook client access, Outlook Web App, and
Outlook Anywhere goes through the Client Access server role on the
hybrid server. Organization relationship features between the
on-premises and cloud-based organizations, such as free/busy
sharing, are also handled by the Client Access server role on the
hybrid server.
Learn more at: Understanding Client Access
- Hub Transport server role The Hub
Transport server role on the hybrid server handles all mail flow
between the on-premises and cloud-based Exchange organizations. If
required, it can also be configured to handle message routing
between the on-premises organization and the Internet. It helps to
secure transport communication between the on-premises and
cloud-based organizations, as well as handling transport rules,
journaling policies, and message delivery to user mailboxes in a
hybrid deployment.
Learn more at: Overview of the Hub Transport Server Role
Hybrid Server Functionality
The hybrid server provides several important functions for your on-premises organization in a hybrid deployment:
- Federation The hybrid server enables
you to create a federation trust for your on-premises organization
with the Microsoft Federation Gateway. The Microsoft Federation
Gateway is a cloud-based service offered by Microsoft that acts as
the trust broker between your on-premises organization and the
cloud-based organization. Federation is a requirement for creating
an organization relationship between the on-premises and the
cloud-based organizations.
Learn more at: Understanding Federation
- Organization relationships The hybrid
server enables you to create organization relationships between the
on-premises and cloud-based organizations. Organization
relationships are required for many other services in a hybrid
deployment, including calendar free/busy information sharing,
message tracking, and mailbox moves between the on-premises and
cloud-based organizations.
Learn more at: Understanding Federated Delegation
- Message transport The hybrid server is
responsible for message transport between the on-premises and
cloud-based organizations in a hybrid deployment. Using Send and
Receive connectors, it serves as the connection endpoint for
incoming messages from the cloud-based organization.
Learn more at: Understanding Transport
- Message transport security The hybrid
server helps to secure message communication between the
on-premises and cloud-based organizations by using the Domain
Security functionality in Exchange 2010. Security can be increased
by using mutual transport layer security authentication and
encryption for message communications.
Learn more at: Understanding Domain Security
- Outlook Web App The hybrid server
supports configuring a single URL endpoint for external connections
to on-premises and cloud-based mailboxes. For on-premises
mailboxes, the hybrid server can be configured to automatically
redirect user Outlook Web App requests to your Exchange 2010
mailbox server. For cloud-based organization mailboxes, the hybrid
server can be configured to automatically display a link to the
Outlook Web App endpoint on the cloud-based organization.
Learn more at: Understanding Outlook Web App
Hybrid Server Topology
The hybrid server is configured much like an Exchange 2010 server would be configured in your existing Exchange 2010 organization. Using the Client Access and Hub Transport server roles, the hybrid server is responsible for many services that are similar to ones provided by your existing Exchange 2010 Client Access servers. The difference is that the hybrid server responsibilities are limited primarily to hybrid deployment-related messaging between the on-premises and cloud-based organizations. The following table describes briefly the changes in services after configuring a hybrid deployment.
Service | Before hybrid server configuration | After hybrid server configuration | Description |
---|---|---|---|
Internal message transport (inbound and outbound) |
Exchange 2010 Hub Transport server |
Exchange 2010 Hub Transport server and Hybrid server |
The hybrid server handles message transport for communication between the on-premises and cloud-based organizations. Exchange 2010 Hub Transport servers handle message transport within your Exchange organization. |
External message transport (inbound and outbound) |
Exchange 2010 Edge Transport server |
Exchange 2010 Edge Transport server |
The MX (mail exchange) record for the domain will remain pointed to the Exchange 2010 Edge Transport server. |
Outlook Web App public URL |
Exchange 2010 Client Access server |
Hybrid server |
The hybrid server redirects Outlook Web App requests to the publicly accessible endpoint on the Exchange 2010 server. |
Hybrid Server Software
Service Pack 1 (SP1) for Exchange Server 2010 provides the base for hybrid deployment functionality. You must update the designated Exchange 2010 hybrid server to Exchange 2010 SP1.