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How to do this:
1) Log into the web management tool via port 5000 or 5001.
2) Go to Control Panel -> "Security" -> Select the "Firewall" Tab
3) Click Create. The "Create Firewall Rules" window will come up
4) Ports -> All
5) Source IP -> Subnet
6) IP Address: 18.0.0.0
7) Subnet Mask: 255.0.0.0
8) Action -> Allow
9) Click OK
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