Our methodology in this tutorial is to take a "bottom up" approach.
We start by checking the really low-level stuff first, then gradually work our way up to higher levels.
Easy to follow howto on setting up a mail server with unlimited users and domains, with IMAP access, anti-spam, anti-virus, secure authentication, encrypted traffic, web mail interface and more.
Based on an Ubuntu distribution platform, but instructions are distro generic.
The most common use is for Fibre Channel (FC) Storage Area Network (SAN). The multipathing layer sits above the protocols (FCP or i SCSI), and determines whether or not the devices discovered on the target, represent separate devices or whether they are just separate paths to the same device.
Device Mapper (DM) is the multipathing layer for Linux that performs this function.
As error reports go, this is on a par with the classic Apollo 13 line "Houston, we've had a problem", though a little less life-threatening.It is easy to follow, but you end up with a powerful secure mail server.The server accepts unlimited domains and users, and all mail can be read via your favourite clients, or via web mail. Look at my references, look at Postfix.org's howtos, read the excellent books available (E.g.Multipath connectivity is possible where multiple connection paths exist between a server and a storage unit (Logical Unit (LUN)) within a storage subsystem.This "dual path" configuration can be used to provide redundancy or increased bandwidth.If you found this howto very useful, spread the word and help others?