On 10/06/2017 20:03, Philip Paeps wrote:
On 2017-06-09 21:10:12 (+0100), Dominic Raferd
<domi...@timedicer.co.uk> wrote:
On 9 June 2017 at 20:45, Steve Jenkins <st...@stevejenkins.com> wrote:
I've got a Postfix server hosting a lastname.org domain name for
family members.
I use virtual aliasing to forward inbound mail for family members to
third-pary mail providers (mostly gmail, but a few yahoo and aol, too).
I've also created user accounts on the server for a very small
handful of immediate family members (4 people) so they can
authenticate (via TLS) send email as firstn...@lastname.org (which
is properly DKIM signed and will pass an SPF check).
I do not provide any mail storage or retrieval on the server (no POP
or IMAP) for any family members.
This has worked fine for years, but now I'm starting to see warnings
in the Postfix log from Gmail, stating that the server is being
rate-limited because of unsolicited messages. I presume that Gmail
is sensing SPAM being sent to the @lastname.org accounts, which gets
forwarded to the family member's Gmail account. I don't do any spam
checking or filtering on the Postfix server.
So my questions are:
1) What's the best way to forward family members' incoming mail to
Gmail (and other mailers)?
2) My Postscreen and main.cf sender restrictions are rejecting a
fair amount of inbound spam, but apparently not enough to keep Gmail
happy.
3) Should I consider setting up SpamAssassin with some very low
thresholds to pick up the obvious stuff?
I have a not-dissimilar setup and I have various fixes to minimise
Gmail's upset. But I guess the first q is whether you need to be
worried about the 'rate-limited' messages. If you have a low volume
of incoming emails anyway a bit of rate-limiting is hardly likely to
be a problem.
The rate-limiting may not be a big problem long-term but eventually
all email coming from you will be filed as spam. And then users will
blame you for that ...
I certainly assumed the same when designing my system, which takes a
range of measures to minimise such emails - both spam/virus blocking of
its own, and reacting swiftly to any messages received back from Gmail.
I was not brave enough to ignore Gmail's rate-limiting (and other)
messages and see what if anything happened next (like the OP we have
very low volumes of legitimate incoming mail). All I can say is that
during the several months it took me to 'perfect' the system, we weren't
blocked by Gmail nor were our forwarded emails filed by Gmail as spam.
(Gmail continues to provide a good 'final spam filter' service for us
after the more egregious rubbish has been filtered out by our own system.)
If someone has direct experience of uniform blocking and/or spam-filing
by Gmail (against an 'innocent' forwarder) then I would be interested
(and feel that my work was not after all a waste of time...)