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Cisco Systems IntelligentGigabit Ethernet Switch Modules for the IBMBladeCenter, Software Configuration Guide
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Chapter12 Configuring VLANs
Configuring VLAN Trunks
Beginning in privileged EXEC mode, follow these steps to modify the allowed list of an IEEE
802.1Q trunk:
To return to the default allowed VLAN list of all VLANs, use the no switchport trunk allowed vlan
interface configuration command.
This example shows how to remove VLAN 2 from the allowed VLAN list:
Switch(config)# interface gigabitethernet0/17
Switch(config-if)# switchport trunk allowed vlan remove 2
Switch(config-if)# end
Switch#
Changing the Pruning-Eligible List
The pruning-eligible list applies only to trunk ports. Each trunk port has its own eligibility list. VTP
pruning must be enabled for this procedure to take effect. The “Enabling VTP Pruning” section on
page 13-13 describes how to enable VTP pruning.
Beginning in privileged EXEC mode, follow these steps to remove VLANs from the pruning-eligible
list on a trunk port:
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Enter interface configuration mode and the port to be configured.
Step3 switchport mode trunk Configure the interface as a VLAN trunk port.
Step4 switchport trunk allowed vlan {add |
all | except | remove} vlan-list
(Optional) Configure the list of VLANs allowed on the trunk.
For explanations about using the add, all, except, and remove keywords,
see the command reference for this release.
The vlan-list parameter is either a single VLAN number from 1 to 4094
or a range of VLANs described by two VLAN numbers, the lower one
first, separated by a hyphen. Do not enter any spaces between
comma-separated VLAN parameters or in hyphen-specified ranges.
All VLANs are allowed by default.
Step5 end Return to privileged EXEC mode.
Step6 show interfaces interface-id switchport Verify your entries in the Trunking VLANs Enabled field of the display.
Step7 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Enter interface configuration mode, and select the trunk port for which
VLANs should be pruned.