sendmail help?
Peter Risdon
peter at circlesquared.com
Thu Jan 22 06:55:32 PST 2004
fbsd_user wrote:
>I think you are barking up the wrong tree.
>I don't think you understand how your ISP works.
>ISP's do not allow direct smtp access to their email servers,
>they consider it an security risk to their environment.
>
>
Sorry, this isn't true. But they don't operate open relays. There are a
number of ways to limit use to valid customers, such as only relaying
for computers with ip addresses in a particular range or subnet or, as
in this case, some form of authentication. If you have a dsl connection,
you sometimes _have to_ send outgoing mail via your ISP's smtp servers.
Some ISPs actually block all outgoing smtp traffic that is NOT routed
through one of their servers. In other cases, ip address blocks used for
DSL connections get blacklisted. I've just come across an example where
this has happened with a major US academic institution and to quote
their security team anonymously:
<quote>
We've received many complaints from our staff about spam which came
directly from poorly administered/hacked machines in this particular
"domainname.obscured.com" range, so we've blocked it. If you can arrange
with someone else (ISP-name-obscured, for instance) to have your outbound
e-mail sent through their mail servers, then we can accept your e-mail,
but we no longer accept e-mail sent directly to us from mail servers
sitting on dialup/DSL/cable/broadband/pooled connections.
</quote>
I've been routing outgoing e-mail via the smtp servers of various ISPs
for years.
PWR.
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