Chapter 11
Configuring VLAN Trunks on Fast Ethernet and Gigabit Ethernet Ports
Port
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4/1
Console> (enable)
Example VLAN Trunk Configurations
The following sections contains examples of a VLAN trunk configurations:
For examples of configuring trunk links between switches and routers, refer to the Layer 3 Switching
Note
Software Configuration Guide—Catalyst 5000 Family, 4000 Family, 2926G Series, 2926 Series, 2948G,
and 2980G Switches publication.
802.1Q Trunk over a Gigabit EtherChannel Link Example
This sample configuration shows how to configure an 802.1Q trunk over a Gigabit EtherChannel link
between two switches with 802.1Q-capable hardware. (Use the show port capabilities command to see
if your hardware is 802.1Q-capable.)
Figure 11-1
Figure 11-1 IEEE 802.1Q Trunk over Gigabit EtherChannel Link
Note
For complete information on configuring Gigabit EtherChannel, see
EtherChannel and Gigabit EtherChannel."
To configure the switches to form a four-port Gigabit EtherChannel bundle, and then configure the
EtherChannel bundle as an 802.1Q trunk link, follow these steps:
Make sure that all ports on both Switch A and Switch B are assigned to the same VLAN. This VLAN is
Step 1
used as the 802.1Q native VLAN for the trunk. In this example, all ports are configured as members of
VLAN 1.
Switch_A> (enable) set vlan 1 2/3-6
VLAN
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1
Switch_A> (enable)
78-15486-01
Vlans in spanning tree forwarding state and not pruned
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2-6,10,20,50,100,152,200,300,400,500,521,524,570,776,802,850,917,999
shows two switches connected through four 1000BASE-SX Gigabit Ethernet ports.
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Switch A
2/4
2/5
2/6
Gigabit EtherChannel
IEEE 802.1Q trunk link
Mod/Ports
2/3-6
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide
3/3
Switch B
3/4
3/5
3/6
Example VLAN Trunk Configurations
Chapter 6, "Configuring Fast
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Release 8.1
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