how to install postfix on my 11.10 box with everything else in place?

[Rashkae]

On 11/08/2011 11:02 AM, Robert P. J. Day wrote:
>    openly admitting i'm not an email admin expert, i have a running
> 11.04 system with email running nicely -- "fetchmail" to get my mail,
> "alpine" as my reader and, underneath it all, postfix.
>
>    i want to finish moving everything from this current system to the
> new one, and the last thing left to move is the ability to get and
> send email.
>
>    i've copied over all of mail/, mbox, .addressbook*, .pinerc,
> installed fetchmail and alpine, and all that's left to do is install
> and configure postfix.
>
>    this *shouldn't* be hard since my .fetchmailrc and .pinerc files
> pretty much configure everything i need to know, i just need to drop
> in a basic postfix, correct?  so given my fairly basic setup, when i
> install postfix on the 11.10 system, which selection do i make:
>
>    No config
>    Internet Site
>    Internet with smarthost
>    Satellite system
>    Local only
>
> as i read it, i want either choice 2 or 3 but i'm not sure which.
> advice?
>
> rday
>
The choice really only affects how e-mail is sent out from your system 
to other hosts on the Internet.  Most people now configure their e-mail 
client program (alpine in your case) to connect to the smtp server of 
their ISP, in which case, this won't matter at all.  You could even 
choose Local Only to make sure Postfix isn't trying to send out anything 
internet side.

However, if you want postfix to be able to deliver messages to the 
Internet, then you are correct, choice 2 or 3.

I still use choice 2, which means Postfix on my system takes care of 
delivery.  I do this because I'm a stubborn, anti-social old goat.  
There are 3 problems with this:

1. Some ISP's block port 25, (as a means to block spam and e-mail 
transmitted virii from originating from their network.).  If that's the 
case, that takes option 2 off the table entirely.  Postfix can't deliver 
e-mail through blocked port 25.

2.  Some mail servers actively reject e-mail originating from ISP dynic 
IP range.  This was somewhat troublesome a year or 2 ago, though it 
seems most blocklists no longer do this.

3. You have to be a bit more savvy about configuring some details of 
postfix, such as a viable hostname.  Leaving postfix identifying itself 
as the default localhost.localdomain (or something similar,) while 
perfectly legal in e-mail rfc, will get you blacklisted on spam RBL 
blocklists.

Internet with Smarthost means postfix will hand off delivery of the 
e-mail to the ISP smtp server.  This should be straightforward if your 
ISP accepts plain e-mail on their own port 25 for forwarding.  However, 
ISP's increasingly require some kind of authentication for outgoing 
e-mail, even when it originates from one of their IP's (again, to combat 
those evil self mailing virii.)  If your ISP smtp server requires 
authentication, then I'll have to defer to someone else for instructions 
on how to configure it.