zyxel 8-port 2.5g multi-gigabit unmanaged switch

Hi @Lefty_Insider

Let's clarify your setup and objectives:

1. Router as NAT and DHCP Server: You want your router to act as a NAT and DHCP server while your ISP modem functions as a bridge.
2. 2.5G Internal Connections: You aim for local devices to connect at 2.5G within your internal network.
3. 1G Internet Speed: Your ISP provides a maximum online speed of 1G.

Issue with Current Setup:

The LAN and WAN traffic from your Netgear router are being mixed on an unmanaged switch, which can lead to DHCP conflicts and inefficient handling. This is likely the reason why your router is not obtaining the IP correctly.

Two options to solve it:

1. Change Topology to modem → router → unmanaged switch as the illustration below. This setup avoids WAN and LAN traffic mixing and allows proper management of IPs.
   
   1. In case your modem and router are far from each other, you may consider adding the coupler between them as suggested by PeterUK. The setup would then be as follows:
      
2. Upgrade to Managed Switch: If you prefer maintaining the current order (modem → switch → router), a managed switch is necessary to set up VLANs for segregating WAN and LAN traffic.
   
   

Importantly, whatever solution you choose, your local devices will only achieve 2.5G speeds under the switch. When traffic reaches the router's 1G LAN port, it will be limited to 1G regardless of the WAN port's 2.5G capability.