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cannot telnet to port 25 from another machine

Posted on 2013-05-29
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Last Modified: 2013-05-29
I have done the following but can sendmail from local but cannot send email&telnet port 25 from anther machine:

- disabled firewall
[root@officemail xinetd.d]# iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
[root@officemail xinetd.d]#


add in /etc/mail/access:
10.128                          RELAY
10.129                          RELAY


makemap hash /etc/mail/access < /etc/mail/access



vi /etc/mail/sendmail.mc
changed to DAEMON_OPTIONS(`Port=smtp,Addr=0.0.0.0, Name=MTA')dnl

m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf
service sendmail stop
killall -HUP sendmail
service sendmail start


[root@officemail ~]# telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
220 officemail ESMTP Sendmail 8.13.1/8.13.1; Wed, 29 May 2013 16:59:55 +0800
quit
221 2.0.0 officemail closing connection
Connection closed by foreign host.
[root@officemail ~]# netstat -vat
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address               Foreign Address             State
tcp        0      0 *:936                       *:*                         LISTEN
tcp        0      0 *:sunrpc                    *:*                         LISTEN
tcp        0      0 *:auth                      *:*                         LISTEN
tcp        0      0 *:smtp                      *:*                         LISTEN
tcp        0      0 *:ssh                       *:*                         LISTEN
tcp        0     52 ::ffff:10.129.146.253:ssh   ::ffff:10.129.146.98:3458   ESTABLISHED
tcp        0      0 ::ffff:10.129.146.253:ssh   ::ffff:10.129.146.98:2058   ESTABLISHED
...
[root@officemail ~]#



=============

but from another pc in the same subnet:

G:\>telnet 10.129.146.253 25
Connecting To 10.129.146.253...Could not open connection to the host, on port 25
: Connect failed

G:\>


how come?

Thanks!
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Question by:Hoboly
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2 Comments
 
LVL 38

Accepted Solution

by:
Gerwin Jansen, EE MVE earned 2000 total points
ID: 39203996
Any firewall / antivirus software installed on that PC?

Have a look in the antivirus log file, it could be blocking port 25.
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Author Closing Comment

by:Hoboly
ID: 39204016
Great! haha
you're right
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