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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. If it helps, get in the habit of just clicking on the "Save" button whenever you make any change.
LAN 1 and LAN 2
If you've connected both Ethernet connections of your Ethernet connections are being usedSynology to the Internet, you will need to apply these settings to the firewall settings of each EACH Ethernet LAN cards. On the tab level on the far right side you'll see a pull down menu. Select LAN 1 or LAN 2 to configure the appropriate ethernet port.