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Old 05-24-2017, 05:16 PM   #1
NotionCommotion
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What might be blocking sockets only on certain ports?


I have a socket server listening to 0.0.0.0:80. I can connect to it from a socket client operating on another machine using 1.2.3.4:80 (where 1.2.3.4 is the server's IP).

Then I change from port 80 to 1337, and can no longer connect. The firewall is disabled. But I can connect if the client is operating on the same machine as the server.

It is a new server operating Centos7. My old Centos6 server did accept connections.

What should I investigate? Thank you
 
Old 05-24-2017, 05:35 PM   #2
hydrurga
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Is SELinux blocking access to the port?
 
Old 05-24-2017, 06:58 PM   #3
NotionCommotion
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Quote:
Originally Posted by hydrurga View Post
Is SELinux blocking access to the port?
Damn that SELinux! I bet you are right.

I've never messed around with it much. In the past, I always disabled it, but really wanted to give it a closer look and determine whether I start using it.
 
Old 05-24-2017, 09:11 PM   #4
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Nope, sestatus shows SELinux status as being disabled. I was sure you were right!
 
Old 05-24-2017, 10:53 PM   #5
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Turned out to be a physical firewall above my virtual server.
 
Old 05-25-2017, 03:36 AM   #6
hydrurga
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Quote:
Originally Posted by NotionCommotion View Post
Turned out to be a physical firewall above my virtual server.
Glad you found the problem.

Can you mark the thread as "Solved"? (see "Thread Tools" at the top of the thread)

Onwards and upwards!
 
  


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