On 4/7/2011 8:48 PM, jeremy.als...@imap-mail.com wrote:
Hi everybody.
I've been reading up how to install a mailserver for my office. At the
local computer users group I was told about using PostFix on an Ubuntu
system instead of Microsoft Exchange Server on Windows. I saw a demo at
the user group, and thought it's worth a real look. They told us about
this List as a User Community resource.
I want to just install a mailserver that listens on the Static address
Comcast gave me, protects against these bots, spam and viruses, and then
delivers it.
So far I've only been reading the website documentation. I ordered a
book too that should get here to Topeka in a few days. The book looked
old and I'm a bit worried it'll be out of date. But for learning
technology I like a good book with examples I can follow.
On the website, I got to an article "Postfix Before-Queue Content
Filter" at http://www.postfix.org/SMTPD_PROXY_README.html that looks
like it does what I want. But I'm confused. It has boxes in the
diagram there for 3 servers.
Why 3? Do I need to have multiple computers to run this server?
[SNIP]
Let me just clear up one higher level issue and others can take it from
there. A server is not a physical machine although colloquially, people
often use the term ambiguously, which is OK if the context is clear. A
server is a process (or group of related processes) combined with access
to a host's resources that together, serve a particular purpose. This
purpose is often served to other Internet-conencted nodes; the service
is usually offered on a dedicated port. A physical machine can be
unambiguously called a host.
Server processes avoid conflicting with one another by using different
dedicated "listening" ports on the same host. These ports must be
well-known to the relevant clients, or "users", of that service.
Even a simple modern desktop PC can easily run (host) many server
processes. Postfix is especially economical in this regard especially if
configured in a trimmed-down way. Especially compared to anything in the
Microsoft world. No need to buy new hardware.
If you're just learning about this kind of thing, the learning curve is
going to be fairly long. This is just fair warning, not an admonishment.
I would quote a recent message:
> I have a suggestion. If you're not familiar with Postfix, don't
try to use all the bells and whistles the first time. Use the
basic features first, and add advanced features over time as
you become more familiar with the system.
Wietse
Then you might try:
http://www.postfix.org/MULTI_INSTANCE_README.html to get the background
of multiple Postfix server processes running on one host.
-Daniel
