Layer 2 forwarding configuration, Configuring general layer 2 forwarding, Working mechanism – H3C Technologies H3C SecBlade NetStream Cards User Manual
Page 115: Configuration procedure, Configuring inline layer 2 forwarding

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Layer 2 forwarding configuration
This chapter includes these sections:
•
Configuring general Layer 2 forwarding
•
Configuring inline Layer 2 forwarding
•
Configuring inter-VLAN Layer 2 forwarding
Layer 2 forwarding falls into the following categories: general, inline, and inter-VLAN.
Configuring general Layer 2 forwarding
Working mechanism
If the destination MAC address of an incoming packet matches the MAC address of the receiving Layer
3 interface, the device forwards the packet through that interface. If not, the device performs general
Layer 2 forwarding through a Layer 2 interface. The device looks up the MAC address table according
to the destination MAC address of the incoming packet, obtains the outgoing interface, and then
forwards the packet through the interface.
Configuration procedure
General Layer 2 forwarding is enabled by default.
Displaying and maintaining general Layer 2 forwarding
To do…
Use the command…
Remarks
Display general and inline Layer 2
forwarding statistics
display mac-forwarding statistics [ interface
interface-type interface-number ]
Available in any view
Clear all general and inline Layer
2 forwarding statistics
reset mac-forwarding statistics
Available in user view
Configuring inline Layer 2 forwarding
Working mechanism
The inline Layer 2 forwarding feature comprises the following types: forward, reflect, and blackhole.
•
Forward type: A packet coming from one interface goes out of another. The packet is forwarded
through the specified incoming and outgoing interfaces, rather than through looking up the MAC
address table. A complete configuration contains an ID, which uniquely identifies an inline Layer 2
forwarding entry, and two interfaces.
•
Reflect type: A packet is forwarded through the interface that received the packet. A complete
configuration contains an ID, which uniquely identifies an inline Layer 2 forwarding entry, and one
interface.