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Telnet working for Localhost, but not host ip

Posted on 2010-11-22
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Last Modified: 2012-08-13
I am trying to understand why a SMTP service on my box for port 940 can be accessed via localhost by not my box's IP.  I've checked my firewall, etc.

Please understand my question is regarding network configuration, not email services.

My question is, what could be blocking this access ?

[$ telnet localhost 940
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 server1.XXXXXXXXXXt ESMTP Postfix
quit
221 2.0.0 Bye
Connection closed by foreign host.
$ ifconfig
eth0      Link encap:Ethernet  HWaddr 00:26:18:4A:CB:DA  
          inet addr:192.168.1.57 Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::226:18ff:fe4a:cbda/64 Scope:Link

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host

telnet 192.168.1.57 940
Trying 192.168.1.57...
telnet: connect to address 192.168.1.57: Connection refused
 
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Question by:Sarge516
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Assisted Solution

by:jackiechen858
jackiechen858 earned 1600 total points
ID: 34190498
Still It probably is a email service configuration, not network configuration.

run
 netstat -nap | grep :940 | grep LIST

It will tell you which process is listening on port 940, if you see  a "127.0.0.1:940", that means this service is configured to only listen on localhost. You will need to modify the email service to let it listen on "0.0.0.0:940"
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Assisted Solution

by:Ernie Beek
Ernie Beek earned 400 total points
ID: 34190543
Did you check 'mynetworks' in /etc/postfix/main.cf ?
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LVL 7

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jackiechen858 earned 1600 total points
ID: 34190630
Edit /etc/postfix/main.cf and change the line to "inet_interfaces = all" then restart Postfix
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Author Comment

by:Sarge516
ID: 34191463
Thanks, all the suggestions above helped, esp the last.

Sarge
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