Force DHCP if the 4G router has a conflict with the Ethernet router.
When a 4G router first connects to a cellular network, the carrier will assign it an IP address to access the Internet. By default, the router is set to use DHCP to obtain an IP address automatically.
However, sometimes the router may get an IP address that actually belongs to itself – this is known as an IP loopback address. When this happens, the router won’t function properly because its own IP address points back to itself.
Enabling “Force DHCP” on the 4G router tells it to renew its IP address by requesting a new one from the carrier’s DHCP server. This forces the router to get a new, valid IP address from the network and resolves the loopback issue.
How to enable “Force DHCP” on the 4G router.
1. Log in to the router admin on a web browser. For example, the default router IP of the EZR3x series router is 192.168.30.1. The router IP of the EZR2x series router router is 192.168.20.1.
2. You can go to “Network > Interfaces > LAN: Edit”.
3. Scroll down to the DHCP server section, click the check box of “Force” under the tab of “Advanced Settings”. Then click the “Save & Apply” button on the right bottom corner and reboot the router.
Please reboot both the 4G router and the Ethernet router after changing the settings. You can also refer to the below demo video. https://youtu.be/M9jdFrUuwGM