- Navigate to Interfaces | OPT1.
- Check the Enable Interface checkbox:
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- Set Description to DMZ.
- Set IPv4 Configuration Type to Static IPv4.
- Enter an IPv4 Address and the CIDR. In our case, we will use 192.168.2.1 and select 24 from the CIDR dropdown list.
- Leave IPv4 Upstream gateway set to None.
- Leave the Block private networks and Block bogon networks checkboxes unchecked (they should be unchecked by default).
- When you are done making changes, click on the Save button. When the page reloads, click on the Apply Changes button.