Cisco WS-C2980G-A Software Guide - Page 231
Configuring VLAN Trunks on Fast Ethernet and Gigabit Ethernet Ports, Understanding How VLAN Trunks Work, Trunking Overview
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11 C H A P T E R Configuring VLAN Trunks on Fast Ethernet and Gigabit Ethernet Ports This chapter describes how to configure Fast Ethernet and Gigabit Ethernet virtual LAN (VLAN) trunks on the Catalyst enterprise LAN switches. Note For complete information on configuring VLANs, see Chapter 10, "Configuring VLANs." Note For complete syntax and usage information for the commands used in this chapter, refer to the Catalyst 4500 Series, Catalyst 2948G, and Catalyst 2980G Switches Command Reference. This chapter consists of these sections: • Understanding How VLAN Trunks Work, page 11-1 • Default Trunk Configuration, page 11-5 • Configuring a Trunk Link, page 11-5 • Disabling VLAN 1 on a Trunk Link, page 11-8 • Example VLAN Trunk Configurations, page 11-9 Understanding How VLAN Trunks Work The following sections describe how VLAN trunks work on the Catalyst enterprise LAN switches. Trunking Overview A trunk is a point-to-point link between one or more switch ports and another networking device such as a router or a switch. Trunks carry the traffic of multiple VLANs over a single link and allow you to extend VLANs across an entire network. The Catalyst 4500 series, 2948G, and 2980G switches support IEEE 802.1Q-802.1Q trunking encapsulation. You can configure a trunk on a single Fast or Gigabit Ethernet port or on a Fast or Gigabit EtherChannel bundle. For more information about Fast and Gigabit EtherChannel, see Chapter 6, "Configuring Fast EtherChannel and Gigabit EtherChannel." 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 11-1
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