Hi, I'm using Postfix 2.8.x and trying to configure properly the
submission port 587 in our very new Postfix installation.
I tried to read the doc and
the result is below. The submission port should be used by clients
from both inside and outside of $mynetworks, so it will be exposed to the
rest of the world (spammers, ...). Hope it's a normal idea.
I tried to configure it very restrictive and I'd like to try to kick off
the spammers from the server as soon as possible to avoid stressing the
mailserver, but still allow our normal clients (Thunderbirds, Outloooks)
to send the email. I
don't have so much experiences in this manner, so I don't know for example
if the smtpd_tls_security_level=encrypt is valuable or not - if it makes
the spammer's lifes more difficult (that was the goal of this settings).
I'm also
unsure if the Amavis check is valuable or not - I'm about to remove it.
The next thing I'm unsure is how this restrictive settings will affect the
clients with mobile phone 2G-mobile/edge slow connections.
Sending emails to root@* and *@localhost* is restricted in the global cfg
of the main.cf file.
I know, that at least in some of the options I'm breaking the rules
(smtpd_timeout for example), but according to doc it should work and it's
necessary for me to find a suitable settings.
Please for any comments, suggestions etc.
Best regards, Tomas
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submission inet n - n - - smtpd
-o smtpd_etrn_restrictions=reject
-o smtpd_sasl_auth_enable=yes
-o content_filter=smtp-amavis:[127.0.0.1]:10024
-o syslog_name=submission
-o receive_override_options=no_header_body_checks
-o smtpd_tls_security_level=encrypt
-o smtpd_tls_loglevel=1
-o smtpd_timeout=${stress?10}${stress:30}
-o smtpd_junk_command_limit=${stress?2}${stress:20}
-o smtpd_soft_error_limit=${stress?5}${stress:5}
-o smtpd_hard_error_limit=${stress?7}${stress:7}
-o smtpd_starttls_timeout=${stress?7}${stress:60}
-o address_verify_poll_count=${stress?1}${stress:3}
-o
smtpd_client_restrictions=permit_mynetworks,permit_sasl_authenticated,permit_auth_destination,reject
