Loading ...
Sorry, an error occurred while loading the content.
 

Re: avoiding overload on port 587

Expand Messages
  • Stan Hoeppner
    ... Germany is not the U.S., and neither are Czechoslovakia. The preferred protocol is dictated by availability of connectivity. There are large swaths of
    Message 1 of 54 , Nov 30, 2012
      On 11/30/2012 5:24 PM, Reindl Harald wrote:
      >
      >
      > Am 01.12.2012 00:19, schrieb Stan Hoeppner:
      >> On 11/30/2012 4:48 PM, Reindl Harald wrote:
      >>
      >>> in the real world submission is useless if IMAP is down
      >>> because the client will fail to store in "sent messages"
      >>
      >> In the real world most road warriors use POP, not IMAP, and those with
      >> consistent connectivity that do make use of IMAP do it via web mail. So
      >> the "sent items" folder isn't an issue. Note the OP mentioned "laptop
      >> users" as his submitters, not desktop users. "Laptop" implies roaming,
      >> or he'd have used a different descriptive term.
      >
      > in the real world THSE DAYS especially road warriors use IMAP
      > and not POP3! notebook, workstation, tablet, smartphone

      Germany is not the U.S., and neither are Czechoslovakia. The preferred
      protocol is dictated by availability of connectivity. There are large
      swaths of the U.S., mainly the midwest, that have poor connectivity.
      Road warriors traveling in these areas will prefer POP. I'm sure the
      same is true in other parts of the world with sparse tower population.

      > have fun with your cummunication as business user if you think
      > "sent items" folder isn't an issue

      For many users having a universal "sent items" folder, or INBOX for that
      matter, is impractical. Most of the road warriors I know (and BTW "road
      warrior" by definition is a traveling salesperson using a car and roads
      for movement, not flights between cities) use separate mailboxes on
      their smart phones and laptops. The smart phone account, maybe more
      than one, is used for ad hoc communication with clients, friends,
      family, etc, and sometimes home office personnel. The account used via
      the laptop is for "official business" only. With such a setup a
      "universal" sent items folder is unnecessary, and often unwanted. For
      instance...

      With many companies in the US, the company provides the laptop to the
      road warrior, complete with company mailbox, AND spyware, keystroke
      logger, etc. The road warrior provides his/her own phone, and uses a
      separate public email provider (gmail) specifically to prevent "big
      brother" from seeing all of his/her communications. Here the universal
      sent items folder is absolutely NOT desirable, especially if it resides
      on the company IMAP server, where all emails can be spied upon.

      --
      Stan
    • /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
        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:
      Your message has been successfully submitted and would be delivered to recipients shortly.