Re: ipfw and mail

From: Bob Martin (bob_at_buckhorn.net)
Date: 06/25/04

  • Next message: Len Conrad: "Re: ipfw and mail" 
    Date: Fri, 25 Jun 2004 16:38:21 -0500
To: "Gustavo A. Baratto" <gbaratto@superb.net>

    We don't redirect the mail. We just have the mail server listen on both
    ports. Much easier that way.

    Bob Martin

    Gustavo A. Baratto wrote:

    >Hello guys,
    >
    >some of our users' ISPs don't allow them to use port 25, so they cannot use out mail server.
    >
    >I want to open a new port (2525) and forward all packets from 2525 to 25 so, they can use mail.
    >
    >I tried this in IPFW:
    >0100 119649 44772439 allow tcp from any to me dst-port 25 keep-state
    >0200 0 0 divert 25 ip from any to me dst-port 2525 keep-state
    >0300 103075 35531648 allow ip from me to any keep-state
    >0400 60 4530 deny log ip from any to any
    >
    >
    >If I telnet directly to port 25, I can get the prompt, but if I telnet to port 2525, I get a connection refused.
    >
    >What should I do in ipfw to forward port 2525 to port 25 tranparently?
    >
    >Thanks
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  • Next message: Len Conrad: "Re: ipfw and mail"

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