I currently have a mail server running on a single FreeBSD server. We are going to make some changes to our network, and I want to setup another server to act as a failover for the current mailserver. Ideally the failover server would kick in or become active automatically if the primary is taken off the network.
How do we go about doing this?
Mail server software doesn't matter too much, we can change it to whatever is needed.
Are you using a shared file system via NFS? Why not have both functioning at the same time? postfix, qmail,exim or any other mail server that stores in Maildirs will do. Are you using a directory service of some sorts NIS,NIS+, LDAP, etc.?
There is no shared file system or directory service at the moment, but this could be setup. Would this become a potential point of failure in the system?