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Catalyst 2960 Switch SoftwareConfiguration Guide
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Chapter12 Configuring VLANs
Configuring VLAN Trunks
Figure 12-2 shows two trunks connecting supported switches. In this example, the switches are
configured as follows:
VLANs 8 through 10 are assigned a port priority of 16 on Trunk 1.
VLANs 3 through 6 retain the default port priority of 128 on Trunk 1.
VLANs 3 through 6 are assigned a port priority of 16 on Trunk 2.
VLANs 8 through 10 retain the default port priority of 128 on Trunk 2.
In this way, Trunk 1 carries traffic for VLANs 8 through 10, and Trunk 2 carries traffic for VLANs 3
through 6. If the active trunk fails, the trunk with the lower priority takes over and carries the traffic for
all of the VLANs. No duplication of traffic occurs over any trunk po rt.
Figure12-2 Load Sharing by Using STP Port Priorities
Beginning in privileged EXEC mode, follow these steps to configure the network shown in Figure 12-2.
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Switch A
Switch B
Trunk 2
VLANs 3 – 6 (priority 16)
VLANs 8 – 10 (priority 128)
Trunk 1
VLANs 8 – 10 (priority 16)
VLANs 3 – 6 (priority 128)
Command Purpose
Step1 configure terminal Enter global configuration mode on Switch A.
Step2 vtp domain domain-name Configure a VTP administrative domain.
The domain name can be 1 to 32 characters.
Step3 vtp mode server Configure Switch A as the VTP server.
Step4 end Return to privileged EXEC mode.
Step5 show vtp status Verify the VTP configuration on both Sw itch A and Switch B.
In the display, check the VTP Operating Mode and the VTP Domain
Name fields.
Step6 show vlan Verify that the VLANs exist in the database on Switch A.
Step7 configure terminal Enter global configuration mode.
Step8 interface gigabitethernet 0/1 Define the interface to be configured as a trunk, and enter interface
configuration mode.
Step9 switchport mode trunk Configure the port as a trunk port.
Step10 end Return to privileged EXEC mode.
Step11 show interfaces gigabitethernet 0/1
switchport
Verify the VLAN configuration.
Step12 Repeat Steps 7 through 10 on Switch A for a second port in the switch.
Step13 Repeat Steps 7 through 10 on Switch B to configure the trunk ports
that connect to the trunk ports configured on Switch A.