How to Open Ports in Linux Server Firewall

Step-by-Step Guide

1. 1

   Step 1: SSH into your server as Root: ~ >>;

   Something like "Vim" editor is good because it's nice and easy.
   
   If you use a different editor that is fine, just know that the commands showing are for "Vim." csf >> vim csf.conf Press (Enter) Note:
   This file has a lot of great security settings in it that you can tweak to your needs, but I am not going to be going into those here.
   
   You can read the comments in the file and they do a great job of explaining what each setting does.
   
   Once you have the file open, you will see a "TCP_IN" and "TCP_OUT" section.
   
   It will look like this: ,, Yours may look different so don't panic! It all depends on your configuration. , This is where we are going to add our port. 2095, 2096, 8000[]"   Since we are using "Vim" we need some special commands.
   
   Press the on your keyboard.
   
   This will allow you to enter "Vims"
   -
   - insert
   -
   - mode so you can add text. ,, This will get you out of
   -
   -insert-
   - mode. , Hold the (Shift) key and press ( ; ).
   
   At the bottom, ( : ) should appear with a blinking cursor. , This stands for
   -write and
   -quit. , csf >> service csf restart Press (Enter) You will see this: ,, Don't Worry! These are all IPs that have either been blacklisted or whitelisted and are being put back into the firewall.
   
   This will only take like five seconds (unless you have a huge list). ,
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   Step 2: Get to the directory where the configuration file is for CSF: ~ >> cd /etc/csf Press (Enter) Note: This is where CSF keeps all of its files

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   Step 3: not just the configuration file.

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   Step 4: Open the configuration file so that we can edit it.

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   Step 5: Allow incoming TCP ports TCP_IN = "20

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   Step 6: 8000"  

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   Step 7: Allow outgoing TCP ports TCP_OUT = "20

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   Step 8: 8000" All those numbers there are ports that are currently "open".

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   Step 9: Navigate down to the end of those lines after where you see that 8000 number.

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    Step 10: Type in the port number:  2095

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    Step 11: 8001[]" Do this for the TCP_OUT as well.

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    Step 12: When you are finished

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    Step 13: hold the (Ctrl) key on your keyboard and press the bracket button ( [ ).

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    Step 14: Save and get out of this file.

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    Step 15: Type the letters (w) and (q)

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    Step 16: with no spaces.

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    Step 17: Restart the firewall so that your changes take effect!

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    Step 18: Stopping CSF

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    Step 19: Then you will see (if any were in the blacklist or whitelist) a bunch of IPs flying across your screen.

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    Step 20: When you see this

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    Step 21: You are Done!

Detailed Guide

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