Re: TCP/IP filter & SMTP

From: sharky (sharky@nospam.com)
Date: 09/10/02 

From: "sharky" <sharky@nospam.com>
Date: Tue, 10 Sep 2002 01:43:33 -0700

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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