Chapter 11: Forwarding Database; Overview Of The Fdb; Fdb Contents - Extreme Networks ExtremeWare XOS Guide Manual

11 Forwarding Database
This chapter describes the following topics:
Overview of the FDB on page 249
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FDB Configuration Examples on page 251
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Configuring the FDB Aging Time on page 252
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Displaying FDB Entries on page 252
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MAC-Based Security on page 253
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Multicast FDB with Multiport Entry—Summit X450 Switch and BlackDiamond 8800 Chassis Only on
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page 256

Overview of the FDB

NOTE
See the ExtremeWare XOS Command Reference Guide for details of the commands related to the FDB.
The switch maintains a database of all MAC addresses received on all of its ports. It uses the
information in this database to decide whether a frame should be forwarded or filtered.
This section covers the following topics:
FDB Contents on page 249
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How FDB Entries Get Added on page 250
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FDB Entry Types on page 250
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FDB Contents

Each Forwarding Database (FDB) entry consists of:
The MAC address of the device
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An identifier for the port and VLAN on which it was received
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The age of the entry
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Flags
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Frames destined for MAC addresses that are not in the FDB are flooded to all members of the VLAN.
ExtremeWare XOS 11.3 Concepts Guide
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