1 mac address table management, Overview, Introduction to mac address table – H3C Technologies H3C S3100 Series Switches User Manual

Page 204: Introduction to mac address learning, Mac address table management

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MAC Address Table Management

When configuring MAC address table management, go to these sections for information you are

interested in:

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Overview

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MAC Address Table Management

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Displaying MAC Address Table Information

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Configuration Example

This chapter describes the management of static, dynamic, and blackhole MAC address entries. For

information about the management of multicast MAC address entries, refer to Multicast Operation.

Overview

Introduction to MAC Address Table

An Ethernet switch is mainly used to forward packets at the data link layer, that is, transmit the packets

to the corresponding ports according to the destination MAC address of the packets. To forward packets

quickly, a switch maintains a MAC address table, which is a Layer 2 address table recording the MAC

address-to-forwarding port association. Each entry in a MAC address table contains the following fields:

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Destination MAC address

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ID of the VLAN which a port belongs to

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Forwarding egress port number on the local switch

When forwarding a packet, an Ethernet switch adopts one of the two forwarding methods based upon

the MAC address table entries.

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Unicast forwarding: If the destination MAC address carried in the packet is included in a MAC

address table entry, the switch forwards the packet through the forwarding egress port in the entry.

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Broadcast forwarding: If the destination MAC address carried in the packet is not included in the

MAC address table, tthe switch broadcasts the packet to all ports except the one that originally

received the packet.

Introduction to MAC Address Learning

MAC address table entries can be updated and maintained through the following two ways:

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Manual configuration

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MAC address learning

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