Many Microsoft Exchange 2010 services use the HTTP/HTTPs protocol. The table below presents each service with its own settings:

Service name		Default URL path	Type of client	Persistence
Autodiscover	AS	/autodiscover/	Outlook	N/A
Exchange ActiveSync	EAS	/microsoft-server-activesync/	Mobile phones	Authorization header
Exchange Control Panel	ECP	/ecp/	Web browser	LB cookie (shared with OWA)
Exchange Web Services	EWS	/ews/	3rd-party applications	N/A
Offline Address Book	OAB	/oab/	Outlook	N/A
Outlook Anywhere	OA	/rpc/rpcproxy.dll	Outlook	Source IP
Outlook Web App	OWA	/owa/	Web browser	LB cookie (shared with ECP)

For host names, you can apply various policies:

• One host name for all services: mail.domain.com

• One host name per service: autodiscover.domain.com, owa.domain.com, ews.domain.com, etc...

• A mix of the above: Outlook Anywhere over oa.domain.com and all other services over mail.domain.com

There are three main architecture layouts possible for Exchange 2010 services running HTTP/HTTPs:

• HTTP reverse proxy on HTTP (TCP/80) and TCP forward on HTTPs (TCP/443)

• HTTP reverse proxy on both HTTP and HTTPs, which means activating SSL offloading on HTTPs

• SSL bridging (or re-encryption) to enable HTTP reverse proxy on both HTTP and HTTPs and get connected using HTTPs on the server side

HAProxy can accommodate any configuration you choose from the information above.

For most deployments, a configuration in SSL offloading or in HTTPs forward mode is the simplest way.

For larger deployments (2000+ users in SSL offloading or 1000+ users in SSL bridging), we recommend a combination such as:

• One host name and one VRRP IP for Outlook Anywhere, configured in TCP forward mode for HTTPs

• One host name for all other services, configured in SSL offloading or SSL bridging mode