hi,
I have setup a mail server using postfix. I am behind a router
which has its port 25 open. when i send a mail to my server using
yahoo. Mailer daemon say cannot establish smtp connection (#4.4.1).
Can any one it out its urgent.
Thanks.
justin....

"justin" <justin_skariah@yahoo.com> wrote in news:1144388938.381760.16150
@i40g2000cwc.googlegroups.com:

> hi,
> I have setup a mail server using postfix. I am behind a router
> which has its port 25 open. when i send a mail to my server using
> yahoo. Mailer daemon say cannot establish smtp connection (#4.4.1).
> Can any one it out its urgent.
> Thanks.
> justin....
>
>

What is the domain name you are working with? Without that information,
any that someone gives is purely speculation.

justin wrote:
> hi,
> I have setup a mail server using postfix. I am behind a router
> which has its port 25 open. when i send a mail to my server using
> yahoo. Mailer daemon say cannot establish smtp connection (#4.4.1).
> Can any one it out its urgent.
> Thanks.
> justin....


Some basic troubleshooting steps are:

1. Make sure that Postfix is alive and semi-responding:
From a shell session on the same server that Postfix is running on, type: telnet 127.0.0.1 25
Make sure you get a welcome banner such as:
220 myhostname ESMTP Postfix (2.2.9) ready
Type in: helo world.com
Make sure Postfix responded and doesn't hang.
Type in: quit

2. Make sure that Postfix is listening on your IP address:

Run the command: $ netstat -an | grep :25
and make sure it's listening on 0.0.0.0 or your IP address, such as:
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN

Repeat step #1 above, only using your IP address instead of 127.0.0.1

3. If possible, repeat Step #2 from another system that's on the same network subnet
as the Postfix server.

4. If possible, repeat step #2 from an system on the Internet (on the other side of your firewall).

5. Repeat step #4 using your system's name, instead of it's IP address.

6. See if your domains records are correct in external DNS by querying another's DNS service:
host mydomain.com cs.utexas.edu


--
Greg

I have the same problem.

Step 1 -- Works with 127.0.0.1 or localhost
Does not work with actual IP address of the server
(Verizon)

Step 2 -- Works as long as I give the assigned IP address (192.168..)

telnet actualIP 25 -- hangs up. Same with the name

Thanks
--gr
On Fri, 07 Apr 2006 18:09:53 GMT, Greg Hackney <hackney@swbell.net>
wrote:

>justin wrote:
>> hi,
>> I have setup a mail server using postfix. I am behind a router
>> which has its port 25 open. when i send a mail to my server using
>> yahoo. Mailer daemon say cannot establish smtp connection (#4.4.1).
>> Can any one it out its urgent.
>> Thanks.
>> justin....
>
>
>Some basic troubleshooting steps are:
>
>1. Make sure that Postfix is alive and semi-responding:
> From a shell session on the same server that Postfix is running on, type: telnet 127.0.0.1 25
> Make sure you get a welcome banner such as:
> 220 myhostname ESMTP Postfix (2.2.9) ready
> Type in: helo world.com
> Make sure Postfix responded and doesn't hang.
> Type in: quit
>
>2. Make sure that Postfix is listening on your IP address:
>
> Run the command: $ netstat -an | grep :25
> and make sure it's listening on 0.0.0.0 or your IP address, such as:
> tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN
>
> Repeat step #1 above, only using your IP address instead of 127.0.0.1
>
>3. If possible, repeat Step #2 from another system that's on the same network subnet
> as the Postfix server.
>
>4. If possible, repeat step #2 from an system on the Internet (on the other side of your firewall).
>
>5. Repeat step #4 using your system's name, instead of it's IP address.
>
>6. See if your domains records are correct in external DNS by querying another's DNS service:
> host mydomain.com cs.utexas.edu

gb_xxxx@verizon.net wrote:
> I have the same problem.
>
> Step 1 -- Works with 127.0.0.1 or localhost
> Does not work with actual IP address of the server
> (Verizon)
>
> Step 2 -- Works as long as I give the assigned IP address (192.168..)
>
> telnet actualIP 25 -- hangs up. Same with the name

Then port 25 probably isn't open from a networking standpoint. It's likely either in
your system's firewall rules (such as iptables), or in your internet router.

For example on my home system, I use internet connection sharing, where all my
systems have their own 192.168 address, but appear as a single dynamic IP address on the Internet.
I had to initially configure my connection sharing device to tell it to allow port 25 TCP, and
to tell it which of the 192.168 addresses it should be routed to.

--
Greg

On Sat, 08 Apr 2006 01:53:38 GMT, Greg Hackney <hackney@swbell.net>
wrote:

>gb_xxxx@verizon.net wrote:
>> I have the same problem.
>>
>> Step 1 -- Works with 127.0.0.1 or localhost
>> Does not work with actual IP address of the server
>> (Verizon)
>>
>> Step 2 -- Works as long as I give the assigned IP address (192.168..)
>>
>> telnet actualIP 25 -- hangs up. Same with the name
>
>Then port 25 probably isn't open from a networking standpoint. It's likely either in
>your system's firewall rules (such as iptables), or in your internet router.
>
>For example on my home system, I use internet connection sharing, where all my
>systems have their own 192.168 address, but appear as a single dynamic IP address on the Internet.
>I had to initially configure my connection sharing device to tell it to allow port 25 TCP, and
>to tell it which of the 192.168 addresses it should be routed to.

I use a LINKSYS router, and also have a dynamic IP address thru
Verizon. Similar to your config.

Let us say, I have 3 different machines in my home. They have been
assigned static IP addresses 192.1681.1.101, 192.168.1.102,
192.168.1.103. The mailserver is on 192.168.1.101

I can do telnet from 102 and 103 machines: telnet 192.169.1.101 25 --
successfully. I think that indicates that router is allowing port 25.

But even on the mailserver, if I do "telnet IPaddress 25" (I chec my
IPaddress thru nslookup). it will fail. However, I am able to
successfully do a SSH from any machine (even from my work). That uses
port 22. Does it mean Verizon is blocking port 25 (incoming).

gb_xxxx@verizon.net wrote:

> But even on the mailserver, if I do "telnet IPaddress 25" (I chec my
> IPaddress thru nslookup). it will fail. However, I am able to
> successfully do a SSH from any machine (even from my work). That uses
> port 22. Does it mean Verizon is blocking port 25 (incoming).

A quick google search reveals users complaining that Verizon DSL
does block port 25, except to the official Verizon SMTP relays.

The messages I saw spoke only of outbound email. I dunno if they also
block inbound port 25. You might call them and ask. Good luck with that.

I can't get DSL at home; live out in the sticks. But I do have the
new high speed Verizon broadband wireless Internet service. They don't
block port 25 on mine (yet).

--
Greg