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IMPORTANT: To confirm that the setting is saved, you should see a line with the new firewall setting allowing in all traffic from the MIT 18.0.0.0 IPv4 range and the save "Save" button should be grayed out and no longer click-able. If the save "Save" button is clickable it means you didn't save yet. Remember to save after each change.
Now that we’ve allowed anyone from MIT to access the server it is time to deny access to everyone else.
1) At the bottom of the Control Panel -> Firewall window there should be a line that starts with “If no rules are matched”
2) Click on "Deny access”.
3) Again, remember to save. Fortunately if you attempt to navigate away or close the window without saving, it will let you know again that changes are not saved.
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