Vigor Router provides multiple IP subnets, which allows different groups of LAN clients to use different IP ranges. More IP subnets are available when VLAN (Virtual LAN) is configured to partition the local network. With a switch that supports VLAN tag, devices in different VLANs can all access the router from one LAN port, while the router can differentiate the traffic by the tags they are carrying. This article introduces how to use multi-subnet on Vigor Router with tag-based VLAN, also how to set up a switch to work with the router.
1. Go to LAN >> VLAN, Enable VLAN Configuration. Create VLANs by selecting the LAN Port members and LAN Subnet, enabling VLAN Tag, and entering a unique VLAN ID for each VLAN. In the following example, LAN port 2 is the port to where the switch is going to connect. (Note: It is recommended to have a VLAN that has VLAN tag disabled so that the router still accepts untagged traffic on specific ports.)
The above configuration implies that all the untagged inbound traffic, no matter which LAN port it is coming from, belongs to Subnet LAN 1. And only Port 2 accepts traffic from different VLANs, where traffic tagged "8", "9", "10" belongs to Subnet LAN2, LAN3, LAN4 respectively.
2. At LAN >> General Setup, check the Enable box of LAN 2, LAN 3 and LAN 4. Then click OK to save the configuration and reboot the router. You may edit the detailed network and DHCP configuration from "Details Page".
3. Go to VLAN >> VLAN Membership to create the VLANs accordingly. Add 3 new VLANs with exactly the same VID used on router's VLAN configuration.
4. Configure the port type and egress rule. For the port connecting to the router, port 1 in this example, set Port Type to "S-Custom port" or "C-port" and Egress Rule to "Trunk", to keep the tags while forwarding the frames to the router. For the ports to which PCs are connecting, port 3, 4 and 5 in this example, set Egress Rule to "Access" to remove the tags when forwarding the frames to the PC.
With the above configuration, the device connecting to Port 3, 4 and 5 of the switch should belong to different subnets and obtain different IP addresses. The device connecting to Port 3 of the switch belongs to Router's Subnet LAN2, and should get an IP address in subnet 192.168.2.0/24. The device connecting to Port 4 of the switch belongs to Router's LAN3 Subnet and should get an IP address in subnet 192.168.3.0/24.