Resolution
Two types of bridging configurations are possible on the Catalyst 2948G-L3 switch:
- All ports belonging to a single bridge group
- Groups of ports belong to one or more bridge groups
In the first case, a Layer 3 (L3) configuration is not required because all the ports belong to the same group. However, in the second case, traffic has to be routed between the bridge groups using a Bridge Virtual Interface (BVI).
A BVI is a virtual interface on the L3 switch. BVI acts like a normal routed interface. When using the BVI for routing, asymmetric routing topology could occur. In this routing topology, packets follow different paths, depending on the direction. Asymmetric routing may cause packet flooding, thereby impacting network performance.
For more information on the implications of asymmetric routing topology when bridge groups are configured on the switch, refer to Asymmetric Routing with Bridge Groups on Catalyst 2948G-L3 and 4908G-L3 Switches.
