Configure The Opt Interface For A Local Network - ZyXEL Communications ZyWALL USG 200 Series User Manual

Click Configuration > Network > Interface > Ethernet and double-click the
wan1 interface's entry. Select Use Fixed IP Address and configure the IP
address, subnet mask, and default gateway settings and click OK.
Figure 61 Configuration > Network > Interface > Ethernet > Edit wan1

7.1.2 Configure the OPT Interface for a Local Network

Here is how to set the opt interface for a separate local network. It uses
192.168.4.1 as its IP address and has a DHCP server to distribute IP addresses to
connected DHCP clients.
ZyWALL USG 100/200 Series User's Guide
Chapter 7 Tutorials
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