Michael Peppard <[EMAIL PROTECTED]> wrote:
> > > how can i say qmail, for the normally SMTP(Port 25) use an different Port
> > > (e.g. 800)?
[...]
> > You're aware, of course, that normal clients won't try any port besides 25
> > when trying to send mail to you.
> This is a good question actually... maybe I should rtfm, but can you receive
> mail on port 25 and transport it on another port?
Eh? SMTP uses port 25. Random SMTP daemons on the Internet will be listening
only on port 25. When qmail establishes a connection to a remote SMTP
server, it will have a random local port number, and connect to port 25
on the remote server. You can override the remote host and port for a domain
using smtproutes -- i.e., you can tell qmail "all mail for foo.org should
go to the SMTP daemon listening on port 5128 on host mail.bar.net instead of
port 25 on whatever the MX record for foo.org says".
> This could be useful in pushing through a firewall, in addition to the
> redirection. My next to next task.
Allow connections to port 25 on your mailserver from anywhere, and all
connections originating on your mail server destined for port 25 on any host.
If you use smtproutes pointing to nonstandard port numbers, you'll need
additional rules to allow those outgoing connections.
You may want to read an SMTP primer to get a better understanding of how
Internet mail works.
Charles
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Charles Cazabon <[EMAIL PROTECTED]>
GPL'ed software available at: http://www.qcc.sk.ca/~charlesc/software/
Any opinions expressed are just that -- my opinions.
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