On Fri, 22 Aug 2003, Enkidu wrote:
> I'm running 3.36 and I wonder if anyone could give me a brief rundown
> of what happens when a pop3 user sends an email through exim to the
> wide Internet.
>
> What I do know is that the initial connection is by SMTP to the Exim
> server.
Yes.
> At least, I hope I know that. What happens then? I've read all
> the docs, but currently haven't got my head around it. Does it go to a
> "router"? How does the "router" get chosen to service a particular
> message?
Exim 3 has both "routers" and "directors". Exim 4 has only "routers". It
is easier to understand for that reason (and some others).
*Messages* are not sent to routers/directors, *addresses* are. A message
may have many recipients. Routers (and directors in 3) make decisions.
They determine how the message should be delivered for each recipient
(which transport should be used). For example "this recipient has a
local mailbox; that recipient needs to go to that host via SMTP", etc.
Then then transports actually carry out the work of delivery.
> I prefer to learn by a) reading the docs b) trying things out,
The debugging options are useful when you are trying things out. Check
out the -d option.
> c) go
> back to a), so I'm not that interested in buying books, but I'm open
> to suggestion in this area. I've found that books are useful once
> you've got your head around a few basic concepts - ie you've moved
> from complete bozo to, well, not-so-complete bozo. But I'm open to
> suggestions.
The Exim 4 book contains an introductory chapter about Internet mail in
general (so does the Exim 3 book, but you probably don't want to buy
that at this stage). The Exim manual contains less introductory material
now that the book exists.
> Note for Philip: This is by way of an apology for polluting the list
> with questions about an obsolete release of your software.
You are not the only polluter! But thanks for the apology. It tempted me
into responding (I'm ignoring most Exim 3 posts now, not so much because
of cussedness, but because I've forgotten the answers).
Philip
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
Get the Exim 4 book: http://www.uit.co.uk/exim-book
