Objective

By default, the SF/SG 300 Series Managed Switch operates in Layer 2 mode. In this mode, the switch uses hardware to make forwarding decisions based on the MAC address information in a frame. In Layer 3 mode, the switch analyzes only the IP header segment of a frame using hardware, as opposed to a router analyzing the entire packet with software. A switch operating in Layer 3 mode has low latency, and can be a replacement for other routers with similar throughput. If you would like to know more about the Layer 3 switch evolution, click here.

The objective of this document is to show you how to enable Layer 3 Mode on the SF/SG 300 Series Managed Switch using the graphical user interface (GUI) and command line interface (CLI).

Applicable Devices

- SF/SG 300 Series Managed Switches

Software Version

- 1.4.0.88

Switching to Layer 3 Mode using the GUI

Step 1. Log into the web configuration utility and choose Administration > System Settings. The System Settings page appears.

Step 2. In the System Mode field, select either the L2 or L3 radio button to select which mode the switch will run in. L2 stands for Layer 2 (Data-Link). L3 stands for Layer 3 (Network). The default is L2.

Note: Layer 2 (Data-Link) forwards data based on MAC addresses. Layer 3 (Network) adds a level of intelligence usually found in routers and the ability to route data using IP addresses.

Step 3. Click Apply.

Step 4. A pop-up window will appear warning that changing the system mode will cause the switch to automatically reboot itself, and erase the startup configuration file in process. Click OK to proceed; the switch will reboot.

Switching to Layer 3 mode using CLI

To set the switch to layer 3 mode, use the following command,

SG300#set system mode router

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