fooler
> ----- Original Message -----
> From: "Pong" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Wednesday, March 20, 2002 5:48 PM
> Subject: Re: [plug] SMTP Ports Question
>
>
>>
>>
>> On Wed, 20 Mar 2002, Joon Guillen wrote:
>>
>> > 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)?
>> >
>>
>> when connecting to remote mail servers, the destination port will
>> always be 25 (SMTP standard). while source port will always be above
>> 1023 for qmail running as a non-root process.
>
> i would like to add to this..... root or non-root, it will usually use
> the *ephemeral* ports (short-lived ports usually in the range from 1024
> to 5000) as source port
>
> here's the flow guillen in order for you to understand.
>
> sending email from client to server
>
> Client[IP:tcp ephemeral ports] --> Server[IP:tcp 25]
>
> relaying email from server to another smtp server
>
> localServer[IP:tcp ephemeral ports] --> remoteServer[IP:tcp 25]
>
> fooler.
>
> _
> 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]
Another questions related to port 25 used by smtp, theres some people used
to telnet this port 25, esmtp, how could we deny it without affecting the
recieving and sending of mails. I try to deny it but it affect my receiving
end using ipchains
ipchains -A input -s mynetwork/Subnetmask -d mymailserver 25 -p TCP -y -j
ACCEPT
ipchains -A input -s 0/0 -d mymailserver 25 -p TCP -y -j DENY
sometimes i try to telnet <hostname> 25....
oninz <--{^0^}
-----------------------------------------
This email was sent using SquirrelMail.
"Webmail for nuts!"
http://squirrelmail.org/
_
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]
