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Old 09-29-2004, 03:19 AM   #1
rnj
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smtp problem..telnet to 25


Hi,


When I telnet to port 25

telnet localhost 25


after a few seconds the connection is close by foreign host.

I tried 10 times the same and once in a while it forms a connection with port 25.

Is SMTP running by default on redhat fedora or can it be enabled or disabled by tweaking xinetd?

Please help.

Ta

RnJ
 
Old 09-29-2004, 03:43 AM   #2
markiv_21
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1st it can be enabled and disabled...............2nd why u want telnet by port 25....you can use the default port of telnet........to telnet......u should enable the service telnet..........................
 
Old 09-29-2004, 08:36 AM   #3
mirradric
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I think rnj is using telnet to test for the presence of a listening service at port 25.

If the server is started by xinetd then you can disable it from there.
But if it's a standalone server then you can't disable it from xinetd.

What does netstat -tap show you?
 
Old 09-29-2004, 10:29 AM   #4
chrism01
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SMTP is normally a standalone daemon. You should be able to stop/start it via the menus if you have X-windows running eg Gnome/KDE.
 
Old 09-30-2004, 05:47 AM   #5
rnj
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Unhappy hi guys...

hi

I am using telnet to test the service on port 25..SMTP
SMTP is not running under xinetd..I have configured SMTPS to run under xinetd. Seems to be a standalone server....
I am using Fedora Core 2. When i run nmap..it shows the smtp 25 port open. Why cannot i establish a decent connection to port smtp????

Thx guys.


RnJ
 
Old 10-02-2004, 09:47 AM   #6
mirradric
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Tell me if my understanding of your question is wrong.
You are trying to run SMTPS. you have disabled, or not, the STMP server that comes with fedora and have set up SMTPS to run under xinetd, but you cannot always get a connection, using telnet, to it but nmap shows that the port is open.

So you have 2 (possibly) main questions :

1. Is the server listening at port 25 the SMTPS server?
2. How come you cannot establish a decent connection if it is your SMTPS server.

For the first question, you can try running netstat -tap as root. Look for the program listening at port 25 (smtp). If it is xinetd then it should be for your SMTPS server. Otherwise, some other program is listening at that port and you'll have to stop it somehow.


For the second question, maybe the server is dropping your connection because you cannot complete the ssl handshake. Maybe you can give us more information like the server you are trying to run, exactly what has happened.

You might want to investigate netcat and cryptcat and telnet-ssl for this purpose?

Last edited by mirradric; 10-02-2004 at 09:51 AM.
 
Old 10-03-2004, 07:12 AM   #7
rnj
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if its default smtp of fedora..how to disable it?

hi mirradric,

if its the default smtp of fedora..how does one disable it? Nmap shows smtp running on port 25, whereas xinetd does not have smtp as a service under it. I have configure a file smtps under xinetd which is also listening to port 25 using stunnel. I am able to connect to imap and pop3 decently. Its only the smtp server.

My conf...
Fedora Core 2
Apache web server
Qmail server installed as per qmailrocks with vpopmail,qmailadmin,courier-imap and squirremail.

Please advice.

Cheers,

RnJ
 
Old 10-03-2004, 11:56 AM   #8
chrism01
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You can only have one prog listening on a given port. If you want to use SMTPS, disable SMTP.
 
Old 12-12-2005, 10:06 PM   #9
christopherccv
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please check your firewall weather block the smtp service
 
Old 12-12-2005, 10:16 PM   #10
liamoboyle
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It doesn't sound like a firewall problem; if the firewall was running, you'd get a connection timeout instead, not a connection reset by peer error.

I suspect the problem is like mirradic suggested - you can't establish an encrypted connection using telnet, so after a few seconds of trying to sort things out, the server drops you. Have you tried pointing an actual mail client at the server (after making sure the client is configured to use ssmtp)?
 
  


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