Setting up mail redundancy for a MailEnable environment


Two methods that can be used to create a redundant mail server environment.  Depending on what you are trying to accomplish one of the two configurations outlined below will allow you to either set up your environment so no mail is lost if any downtime occurs, or so mail throughput has no downtime due to any server problems.  Both of the configurations can be implemented together so as to obtain the desired affects in one environment.


The two approaches are:
1. Store Mail While Primary Server is Offline:
The article below, shows how to configure an MX record to have a backup MX.
This will mean that if the primary mail server is offline, that the secondary backup MX will accept the e-mail on behalf of the primary.
To do this, configure the secondary MX mail server with all the domains to host, and use the smart host option for each domain, or in the SMTP service properties so that it is directed to the primary MX mail server.  This way, if the primary goes offline, then the secondary will accept the mail, and queue it until the primary server is back online.
2. Server Redundancy
For total redundancy, whereby if one server goes offline, then the other will totally assume the role of the primary, configure the two servers in a cluster rather than using the smart host option. This way both servers share the same message store and queues and so long as the message store/queue repository is online, messages will be delivered accordingly.
This will also require a clustered IP address for any clients and other servers to connect to. There are many network load balancing switches available on the market that will do this. The MailEnable Enterprise Infrastructure Configuration Guide outlines this approach in detail.


How to configure back up or redundant mail servers:
Article ME020193

How to cluster MailEnable:
Article ME020023

Product:MailEnable (Ent-Any Ent-1.X Ent-2.X)
Class:TRB: Troubleshooting (Configuration or Environment)
Revised:Wednesday, May 4, 2016