RE: telnet/pop3 question

[Antonio Galea <ant9000 netwise it>]

On Mon, 7 Oct 2002, Dave Miller wrote:

> After installing the imap rpm, I can retrieve email with my PC using  POP3
> from my local home linux server. Thank you.  When I try to send mail from
> my PC using Outlook to my Linux server,  it fails. When I test with
> telnet, I find that loop back address looks good, but the real IP address
> gets refused. Why would this be? :
> $ telnet 127.0.0.1 25
> Trying 127.0.0.1...
> Connected to 127.0.0.1.
> Escape character is '^]'.
> 220 goofy.mshome.net ESMTP Sendmail 8.11.6/8.11.6; Mon, 7 Oct 2002
> 15:41:51 -0500
> quit
> 221 2.0.0 goofy.mshome.net closing connection
> Connection closed by foreign host.
> $ telnet 192.168.100.105 25
> Trying 192.168.100.105...
> telnet: connect to address 192.168.100.105: Connection refused
> I think my hosts.allow is OK, since port 110 works OK:
> $ telnet 192.168.100.105 110
> Trying 192.168.100.105...
> Connected to 192.168.100.105.
> Escape character is '^]'.
> +OK POP3 goofy.mshome.net v2000.70rh server ready
> 
> 

The ports that must be allowed are, as you correctly tested, two: port 25 and
port 110. The message "Connection refused" is usually given by the tcp
wrappers library, so I guess your hosts.allow is missing a line like

sendmail: ALL

(maybe something more restrictive), that enables the connection to reach
sendmail.

Another possibility is that your sendmail is only listening on the loopback
interface 127.0.0.1: RedHat default config for sendmail works like that. Try
a netstat to check if that is your problem:

# netstat --inet -an | grep :25
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN

To correct it, have a look at /etc/mail/sendmail.mc, there's a line to
comment out and then you have to generate (with m4) a new configuration.
It's pretty heavily commented, you should find your way around easily.

Ant9000

-- 
_____________________________________________________________________________
Dr. Antonio Galea       N e t   W i s e                 http://www.netwise.it
Sviluppo tecnico     Tecnologie per il Web    Tel 0461.421016 Fax 0461.426021
-----------------------------------------------------------------------------
I have the heart of a child; I keep it in a jar on my desk.
-----------------------------------------------------------------------------
--