Multiple instances of the Mail Connector can be deployed for load balancing and to provide redundant mail paths. As illustrated below, any CMG server can receive messages from any mail server defined in the configuration file, and likewise can relay messages to any of the defined destination servers.
CMG's Mail Connector interprets and honors MX priority settings to intelligently distribute messages in prioritized round-robin fashion. Priority designations run in reverse-numerical order, where the highest priority is 0, and higher priority numbers represent less preferred servers.
When MX resolution is enabled for CMG’s outbound servers, the Mail Connector attempts a connection at the highest priority level, and if unsuccessful attempts a connection with another server (if any) at the same priority level, or at the next lower priority level only if no server at the higher priority level is available. Within each group of servers at the same priority level, the Mail Connector randomly selects a server in the group for its first connection attempt, and then if unsuccessful proceeds to the other servers in random round-robin fashion.
CMG’s Mail Connector is easily configured to work with a hosted Exchange environment such as Microsoft’s Office 365. A CMG connection with a hosted environment is configured in the , and also requires some minor accommodations in server configurations, as noted in the instructions.
There are no performance tips unique to a hosted Exchange configuration with CMG. Hosted Exchange is a slight variation in CMG’s server connection validation code; everything else is treated just like regular message traffic.
NOTE: If coexisting with GroupWise 7: Note that inbound external (internet) mail delivered to GroupWise 7 cannot be routed to Exchange users, due to the way the proxy GWIA receives messages and the way messages are written into the production GWIA. To avoid this problem, you could direct inbound internet mail to Exchange instead.
The process of installing, configuring and activating the CMG Mail Connector consists of these general steps, all of which are explained in more detail below. This process begins with the assumption that the GroupWise and Exchange environments are operational, and that the environments conform to the CMG system requirements specified for the current release of CMG (as documented in the most recent RTM Release Notes).
IMPORTANT: These server reconfigurations should occur only after CMG is started (preceding step). Otherwise the mail servers would (at least briefly) be trying to send mail to a non-existent destination.