For Layer 3 Switch that does not support Dynamic Routing, Gateway Static Route can be used to "bridge" them together. One of the benefit of using Gateway to connect independent Layer 3 Switch is simplicity. There is no need to configure anything else on the Layer 3 Switch, and the Gateway can route traffic from one Layer 3 Switch VLAN to another Layer 3 Switch VLAN. However, the East-West Traffic (i.e. LAN to LAN traffic) is limited by the Gateway Uplink Speed. In scenarioes where Gateway is an entry level model, Layer 3 IP routing can take away some CPU cycles from Gateway doing InterVLAN traffic. This is where Switch Static Route can help the Gateway, it will improve East-West Traffic (i.e. LAN to LAN traffic) as well as allow Switches to utilize many of the Switch-to-Switch capabilities such as LAG.

Switch Static Routing can also be combined with Gateway Static Routing, the Gateway Static Route can serve as an alternate-route to provide physical uplink redundancy between Switches, and LAN to LAN traffic will use Gateway Static Route if the Switch to Switch uplink is not available.

Set Up:

• VLAN 1 is the management VLAN

• One Gateway [IP 192.168.0.1]

• Two Layer 3 Switches (Switch A, and Switch B)

  • Layer 3 Switch A, IP 192.168.0.100 [VLAN 1]

    • VLAN 10, IP 192.168.10.1 [SVI]

    • VLAN 30, IP 192.168.30.100 [SVI]

  • Layer 3 Switch B, IP 192.168.0.200

    • VLAN 20, IP 192.168.20.1 [SVI]

    • VLAN 30, IP 192.168.30.200 [SVI]

Note:

• You can combine Gateway Static Route, with Layer 3 Switch Static Route for LAN traffic Redundancy

• This redundancy does NOT cover Internet fail-over, this only works for InterVLAN traffic between Layer 3 Switches

Gateway <> Switch Uplink:

1. Connect Omada Gateway xLAN Port 1 to Layer 3 Switch A [VLAN 1]

2. Connect Omada Gateway xLAN Port 2 to Layer 3 Switch B [VLAN 1]

Gateway Static Route Set Up:

1. Add Gateway Static Route to Switch A

   1. Transmission > Routing > Create New Route > Route 1 > Status: Enable > Destination IP: 192.168.10.0/24 > Next Hop > 192.168.0.100

2. Add Gateway Static Route to Switch B

   1. Transmission > Routing > Create New Route > Route 2 > Status: Enable > Destination IP: 192.168.20.0/24 > Next Hop > 192.168.0.200

3. Optional - Add Gateway Static Route to Switch C [Can be combined with Gateway Static Route 1]

   1. Transmission > Routing > Create New Route > Route 3 > Status: Enable > Destination IP: 192.168.30.0/24 > Next Hop > 192.168.0.100

Layer 3 Switch SVI Configuration:

1. Configure SVI VLAN 10 and SVI VLAN 30 on Switch A

   1. Devices > Switch A > Config > VLAN Interface > VLAN 10 > Slider: On > Edit > IP Address Mode: Static > IP Address: 192.168.10.1/24 > DHCP Server > Gateway: 192.168.10.1 > Apply > Apply

   2. Devices > Switch A > Config > VLAN Interface > VLAN 30 > Slider: On > Edit > IP Address Mode: Static > IP Address: 192.168.30.100/24 > Apply > Apply

2. Configure SVI VLAN 20 and SVI VLAN 30 on Switch B

   1. Devices > Switch B > Config > VLAN Interface > VLAN 20 > Slider: On > Edit > IP Address Mode: Static > IP Address: 192.168.20.1/24 > DHCP Server > Gateway: 192.168.20.1 > Apply > Apply

   2. Devices > Switch B > Config > VLAN Interface > VLAN 30 > Slider: On > Edit > IP Address Mode: Static > IP Address: 192.168.30.200/24 > Apply > Apply

Layer 3 Switch Static Route Configuration:

1. Add Switch Static Route to Switch A

   1. Devices > Switch A > Config > Static Route > Add > Enable > Destination IP: 192.168.20.0/24 > Next Hop > 192.168.30.200

2. Add Switch Static Route to Switch B

   1. Devices > Switch B > Config > Static Route > Add > Enable > Destination IP: 192.168.10.0/24 > Next Hop > 192.168.30.100

3. Configure VLAN 30 Access Ports in Switch A

   1. Devices > Switch A > Ports > Port X > Edit > Profile > VLAN 30 > Apply

4. Configure VLAN 30 Access Ports in Switch B

   1. Devices > Switch B > Ports > Port Y > Edit > Profile > VLAN 30 > Apply

5. Connect Switch A VLAN 30 Access Port X to Switch B VLAN 30 Access Port Y

Testing Gateway as Back Up Link:

1. Turn Off Switch Static Route.

   1. Devices > Switch A > Config > Static Route > Edit > Disable > Apply

   2. Devices > Switch B> Config > Static Route > Edit > Disable > Apply

2. Configure VLAN 10 Access Port in Switch A

   1. Devices > Switch A > Ports > Port XX > Edit > Profile > VLAN 10 > Apply

3. Connect PC to Port XX [IP 192.168.10.x]

4. From PC, Traceroute to SVI of VLAN 20 192.168.20.1

   1. Traffic should traverse the Gateway IP 192.168.0.1

5. Configure VLAN 20 Access Port in Switch B

   1. Devices > Switch B > Ports > Port YY > Edit > Profile > VLAN 20 > Apply

6. Connect PC to Port YY [IP 192.168.20.x]

7. From PC, Traceroute to SVI of VLAN 10 192.168.10.1

   1. Traffic should traverse the Gateway IP 192.168.0.1

Testing Switch as Primary Uplink:

1. Turn On Switch Static Route.

   1. Devices > Switch A > Config > Static Route > Edit > Enable > Apply

   2. Devices > Switch B> Config > Static Route > Edit > Enable > Apply

2. Configure VLAN 10 Access Port in Switch A

   1. Devices > Switch A > Ports > Port XX > Edit > Profile > VLAN 10 > Apply

3. Connect PC to Port XX [IP 192.168.10.x]

4. From PC, Traceroute to SVI of VLAN 20 192.168.20.1

   1. Traffic should NOT traverse the Gateway IP 192.168.0.1

5. Configure VLAN 20 Access Port in Switch B

   1. Devices > Switch B > Ports > Port YY > Edit > Profile > VLAN 20 > Apply

6. Connect PC to Port YY [IP 192.168.20.x]

7. From PC, Traceroute to SVI of VLAN 10 192.168.10.1

   1. Traffic should NOT traverse the Gateway IP 192.168.0.1

I also have a video guide up showing a more complex connection, which includes the full configuration and testing, and I am using the logical diagram below: