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Re: avoiding overload on port 587

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  • /dev/rob0
    ... Spamassassin can be tailored for the job of submission scanning. The URIBL checks are particularly good at detecting compromised accounts. --
    Message 1 of 54 , Dec 3, 2012
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      On Mon, Dec 03, 2012 at 07:34:13PM -0600, Stan Hoeppner wrote:
      > On 12/3/2012 2:55 PM, mouss wrote:
      > > Le 03/12/2012 10:07, Stan Hoeppner a écrit :
      > >> You might want to look into these as well:
      > >>
      > >> -o content_filter=
      > > ahem? submission or not, it must go through a malware filter.
      >
      > Sorry for the oversight. Yes, one would want to include clamav or
      > other malware checker, but exclude Spamassassin or any spam filter
      > geared toward inbound public mail. Excluding SA reduces load, and
      > prevents mail being scored as spam due to dynamic IP status, etc.

      Spamassassin can be tailored for the job of submission scanning. The
      URIBL checks are particularly good at detecting compromised accounts.
      --
      http://rob0.nodns4.us/ -- system administration and consulting
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    • /dev/rob0
      ... Or better yet: replace it with postscreen. ... To clarify, I meant that if those Outlook Expresses are not yet compromised by malware, they will be, soon.
      Message 54 of 54 , Dec 4, 2012
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        On Tue, Dec 04, 2012 at 07:46:10AM -0600, /dev/rob0 wrote:
        > On Tue, Dec 04, 2012 at 11:59:01PM +1300, Peter wrote:
        > > I would still also set up port 587 on the mail.example.com
        > > IP as submission as well and try to encourage your users (at
        > > least the ones you can) to use port 587 from now on.
        >
        > What I would do, on Linux with IPv4 only, is create the submission
        > port and use an iptables redirect for the alternate IP address:
        >
        > # iptables -vt nat -A PREROUTING -p tcp --dport smtp -d \
        > mail.example.com -j REDIRECT --to-port submission
        >
        > This saves the overhead (system and administrative) of running
        > another smtpd on [mail.example.com]:25; he can leave his "smtp ...
        > smtpd" service alone in master.cf.

        Or better yet: replace it with postscreen.

        > I should also add as a reply to Stan in the other subthread: look
        > above at the first quoted paragraph: "Outlook Expresses setup with
        > ... default configuration."
        >
        > Yikes, bad news, very bad. If not doing content filtering nor
        > policy limitation of submission now, he will be soon. And possibly
        > losing his job in any case. Tomas is not in a good place right now.

        To clarify, I meant that if those Outlook Expresses are not yet
        compromised by malware, they will be, soon.
        --
        http://rob0.nodns4.us/ -- system administration and consulting
        Offlist GMX mail is seen only if "/dev/rob0" is in the Subject:
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