Re: TCP/IP filter & SMTP

From: Ken Schaefer (kenRMV@THISadOpenStatic.com)
Date: 09/10/02 

From: "Ken Schaefer" <kenRMV@THISadOpenStatic.com>
Date: Tue, 10 Sep 2002 18:59:50 +1000

I said "packet sniffer", not "port scanner" :-)

Open up all the ports so that it works. Then fire up NetMon (tool that comes
with Windows2000) and do a packet capture. Then look at all the TCP/UDP
packets and see where they are going/coming. Find out which port it is that
you need to open.

NetMon can be installed from the Add/Remove programs control panel (Windows
Components | Network Utilities(?))

Cheers
Ken 

--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"sharky" <sharky@nospam.com> wrote in message
news:#h15GZKWCHA.2656@tkmsftngp10...
> Thanks, Ken!
>
> I tried that using vbportscan.exe, but I got the same results when the
> server is idle as when I sent mail from the site. It seems that the port
> scanner is only checking listening ports, and maybe the server is sending
> some sort of UDP packet when I send mail (?).
>
> I've got TCP 53 open. This seems to be a UDP issue since this only breaks
> when I close UDP ports. I like Tiny, but it won't work on my particular
> setup.
>
> I appreciate your input anyways.
> - shark
>
>
>
> "Ken Schaefer" <kenRMV@THISadOpenStatic.com> wrote in message
> news:OdSgT6JWCHA.1748@tkmsftngp09...
> > What if you install some kind of packet sniffer and capture the packets
> > going back and forwards? This will tell you what port you'll need to
> > open. -or- install a software application level firewall and see what it
> > pops up (TPF is a good choice: www.tinysoftware.com)
> >
> > Also, if you are using MS SMTP server or Exchange server, you'll need to
> > enable TCP 53:
> > http://support.microsoft.com/default.aspx?scid=kb;en-us;Q263237
> >
> > Cheers
> > Ken
> >
> > --
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > "sharky" <sharky@nospam.com> wrote in message
> > news:ez3lCKHWCHA.1632@tkmsftngp11...
> > > I have enabled TCP/IP filter on all addresses on my web server (yea
me).
> > >
> > > I've got everything working except the UDP filter. I denied access to
> all
> > > UDP services except 88,137,138,53,135 which allows me to browse my
> network
> > > connection to shares, resolve dns, and use RPC - BUT for some reason,
my
> > web
> > > server can no longer find my ISP's SMTP server to send mail from our
asp
> > > formmail. I get the following error:
> > >
> > > WSAHOST_NOT_FOUND
> > >
> > > That doesn't seem right because I've got SMTP (TCP) enabled on TCP,
and
> > DNS
> > > (53) enabled in UDP, and I can't find any other ports that SMTP might
> use.
> > >
> > > If I enable all UDP ports, it works fine. When I deny all UDP ports
> except
> > > the above, it breaks, so it must be some UDP port is needed to use
SMTP
> > from
> > > my web server.
> > >
> > > NOTE: this ONLY happens when I turn off UDP ports, and yes I have
> enabled
> > > SNTP ports on TCP, but that doesn't appear to be the problem because I
> > only
> > > have this problem when I deny UDP ports.
> > >
> > > Has anybody run into this before or have some knowledge on the subject
> > they
> > > can share?
> > >
> > > Gracias!
> >
> >
> >
>
>

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