Cisco WS-CBS3032-DEL Software Configuration Manual page 339

Chapter 11 Configuring Interface Characteristics
Figure 11-1
172.20.128.1
172.20.128.1
When the IP services feature set is running on the switch or the stack master, the switch uses two
methods to forward traffic between interfaces: routing and fallback bridging. If the IP base feature set is
on the switch or the stack master, only basic routing (static routing and RIP) is supported. Whenever
possible, to maintain high performance, forwarding is done by the switch hardware. However, only IPv4
packets with Ethernet II encapsulation are routed in hardware. Non-IP traffic and traffic with other
encapsulation methods are fallback-bridged by hardware.
The routing function can be enabled on all SVIs and routed ports. The switch routes only IP traffic.
•
When IP routing protocol parameters and address configuration are added to an SVI or routed port,
any IP traffic received from these ports is routed. For more information, see
"Configuring IP Unicast Routing," Chapter 45, "Configuring IP Multicast Routing,"
Chapter 46, "Configuring MSDP."
• Fallback bridging forwards traffic that the switch does not route or traffic belonging to a nonroutable
protocol, such as DECnet. Fallback bridging connects multiple VLANs into one bridge domain by
bridging between two or more SVIs or routed ports. When configuring fallback bridging, you assign
SVIs or routed ports to bridge groups with each SVI or routed port assigned to only one bridge
group. All interfaces in the same group belong to the same bridge domain. For more information,
see
OL-13270-06
Connecting VLANs with the Blade Switch
Layer 3 switch
with routing enabled
SVI 1
Host A
VLAN 20
Layer 3 switch
with routing enabled
SVI 1
Blade
server A
VLAN 20
Chapter 47, "Configuring Fallback Bridging."
Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
Understanding Interface Types
SVI 2 172.20.129.1
Host B
VLAN 30
SVI 2 172.20.129.1
Blade
server B
VLAN 30
Chapter 39,
and
11-7