Knowledge Base Connecting Multiple Omada Layer 3 Switch via Omada Gateway
Assumption:
- VLAN 1 is the management VLAN
- One Gateway
- Two Layer 3 Switches (Switch A, and Switch B)
- Layer 3 Switch A, IP x.100 - VLANs 10, 20
- Layer 3 Switch B, IP x.200 - VLANs 30, 40
Many of the early Omada Layer 3 Switch (prior to 2023) doesn't support dynamic routing (i.e. OSPF, IS-IS, RIP v2 or BGP), prior to the SG6x series of Layer 3 Switch. So when implementing multiple independent Omada Layer 3 Switch, each Layer 3 Switch will NOT know how to reach the VLANs that are not "locally" defined. This means that L3 Switch A does not know how to reach VLANs 30 and 40 that are defined on L3 Switch B; and just the same, L3 Switch B does not know how to reach VLANs 10 and 20 that are defined on L3 Switch A. A Switch static route can be added, but to "route" these VLANs without any special configuration to the L3 Switch A and L3 Switch B, these independent L3 Switches can be connected to Omada Gateway and a Static Route can be added in Omada Gateway. With this set up, the Gateway will manage the routing between L3 Switch A and L3 Switch B.
Note: When doing Gateway Static Route, it is not the same as Layer 3 Switch Static Route.
High Level Set Up Steps:
- Connect Omada Gateway xLAN Port 1 to Layer 3 Switch A
- Connect Omada Gateway xLAN Port 2 to Layer 3 Switch B
- Gateway Static Route 1 > VLANs 10/20 > Next Hop > Switch A x.100
- Gateway Static Route 2 > VLANs 30/40 > Next Hop > Switch B x.200
To avoid any conflict, there are also a few nuances to watch out for:
- Be vigilant of using Profile "All" for Gateway and Switch uplink.
With multiple Layer 3 Switches and their defined VLANs, profile "All" will include VLANs defined in all of the Layer 3 Switches.
Depending on implementation, this may or may not be something that is needed across ALL the Layer 3 Switches in the environment. - Create an alternate profile to represent "All" for each Layer 3 Switch.
For example, create new Profile that have VLAN 1 (Untag), VLAN x (Tagged), VLAN y (Tagged) in each L3 Switch
This way, all the VLANs defined in that Layer 3 switch can be configured as uplink/downlink to Access Points and Access Switches. - And because of that, remember that Access Points and Access Switches connected to that L3 Switch, can only provide VLANs in that Layer 3 Switch.
If you would like to see this in action, I have a video demonstrating it as well as how it affects the number of hops based on where the source and destinaton devices are connected. I have also added a sample diagram of how it looks.