6.2 Layer 3 Switching

The two major functions provided by a Layer 3 switch include IP Switching and Routing Path Management. When the switch is set to multilayer mode, it acts as a routing switch, with support for standard IP routing and the ability to pass traffic between VLANs as required. However, when the switch is first set to multilayer mode, no default routing is defined. As with all traditional routers, the routing function must first be configured to work. (RIP).

6.2.1 Initial Configuration

In the default configuration, all ports belong to the same virtual LAN and the switch provides only Layer 2 functionality. So you should first group all the ports that belong to the same subnet into virtual LANs. By separating the switch into different VLANs, the network is partitioned into subnetworks that are disconnected at Layer 2. Network traffic within the same subnet is still switched using Layer 2 switching. And the VLANs can now be interconnected (only as required) with Layer 3 switching. Each VLAN represents a virtual interface to Layer 3. You just need to provide the network addresses for each virtual interface, and the traffic between different subnetworks will be routed by Layer 3 switching.

VLAN Configuration for Layer 3

Note: When operating the switch in multilayer mode, all ports should be defined as untagged, and no VLANs can overlap. You should also assign the same default PVID to the ports at both ends of a link if the VLAN must cross the switches. (See “VLAN Tagging” configuration.) These limitations will be removed for future firmware versions.

WGS3 Layer 3 Switch User’s Manual

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