Hi,

Thanks for the rules.  BTW, is the -y flag equivalent to the --syn flag on
iptables?  Sorry I forgot :P

jOoN


----- Original Message -----
From: "Benj" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, March 20, 2002 5:42 PM
Subject: Re: [plug] SMTP Ports Question


> Joon Guillen wrote:
>
> > Hi,
> >
> > Does the SMTP service use the same port (25) to connect and forward the
> > outgoing e-mails to its designated mail servers or do they use the ports
> > above 1023?  And, will the remote mail server need to respond to it (as
an
> > acknowledgement, or maybe something else)?
>
> Yes, SMTP uses ports 1024 and above to send out mails, and the remote
> mail servers do need to respond to sending client.
>
> > I'm doing firewall rules, and I'd like the rules to be as specific as
> > possible.  I'm using qmail and qmail-smtpd btw.
>
> Here are the rules:
>
> # SMTP client (25)
> # ----------------
>
> ipchains -A input  -i $INTERNAL_INTERFACE -p tcp ! -y \
> -s $SMTP_SERVER 25 \
> -d $INTERNAL_IPADDR $UNPRIVPORTS -j ACCEPT
>
> ipchains -A output -i $INTERNAL_INTERFACE -p tcp \
> -s $INTERNAL_IPADDR $UNPRIVPORTS \
> -d $SMTP_SERVER 25 -j ACCEPT
>
> Note:
> $UNPRIVPORTS="1024:65535"
>
> --
> Benjamin Oris Jr.
> ImagineAsia Digital Animation Studio
> http://www.imagineasia.com
> _
> Philippine Linux Users Group. Web site and archives at
http://plug.linux.org.ph
> To leave: send "unsubscribe" in the body to [EMAIL PROTECTED]
>
> To subscribe to the Linux Newbies' List: send "subscribe" in the body to
[EMAIL PROTECTED]
>

_
Philippine Linux Users Group. Web site and archives at http://plug.linux.org.ph
To leave: send "unsubscribe" in the body to [EMAIL PROTECTED]

To subscribe to the Linux Newbies' List: send "subscribe" in the body to 
[EMAIL PROTECTED]

Reply via email to