Solved

cannot telnet to port 25 from another machine

Posted on 2013-05-29
2
1,252 Views
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!
0
Comment
Question by:Hoboly
2 Comments
 
LVL 38

Accepted Solution

by:
Gerwin Jansen, EE MVE earned 500 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.
0
 

Author Closing Comment

by:Hoboly
ID: 39204016
Great! haha
you're right
0

Featured Post

Use Case: Protecting a Hybrid Cloud Infrastructure

Microsoft Azure is rapidly becoming the norm in dynamic IT environments. This document describes the challenges that organizations face when protecting data in a hybrid cloud IT environment and presents a use case to demonstrate how Acronis Backup protects all data.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Resolve Outlook connectivity issues after moving mailbox to new Exchange 2016 server
Local Continuous Replication is a cost effective and quick way of backing up Exchange server data. The following article describes the steps required to configure Local Continuous Replication. Also, the article tells you how to restore from a backup…
In this video we show how to create a mailbox database in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Servers >> Data…
Nobody understands Phishing better than an anti-spam company. That’s why we are providing Phishing Awareness Training to our customers. According to a report by Verizon, only 3% of targeted users report malicious emails to management. With compan…

830 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question