Russell Nelson <[EMAIL PROTECTED]> writes:
> Right, and any scalable email system is going to use NFS.
Why do you think that?
My experience is quite the contrary, namely that delivering to *any*
shared file system, whether it be NFS or AFS, is fundamentally less
reliable and harder to maintain than delivering mail to independent mail
server machines with their own local storage that serve mail up
exclusively via a mail retrieval protocol like POP or IMAP. Most mail
reading clients these days aren't interested in mounting an incoming
folder from somewhere; they're interested in talking a wire protocol to a
server.
Put some sort of redirection scheme in place to hide what physical machine
a given user's mailbox is on (so that they actually connect to the server
username.pobox.example.com or the like) and use disk mirroring on each
seperate server machine for reliability, and I believe you'll both get
better performance and better uptime than you will from an NFS solution.
It's certainly scaleable; as you fill one user server machine, you simply
add another, and since they're all independent, there are no scaling
factors preventing you from doing that. (You may occasionally have to add
a new mail routing machine as well, but that's hardly a problem.)
I'm strongly of the opinion that the best way to transfer mail is to use a
mail transfer protocol, not to use a file transfer protocol.
--
Russ Allbery ([EMAIL PROTECTED]) <URL:http://www.eyrie.org/~eagle/>
