Defining The Allowed Vlans On A Trunk - Cisco Catalyst 2960 series Configuration Manual

How to Configure VLAN Trunks
Command or Action
Step 9
show interfaces interface-id trunk
Example:
Switch# show interfaces gigabitethernet1/0/2
trunk
Step 10
copy running-config startup-config
Example:
Switch# copy running-config startup-config
Related Topics
Trunking Modes, on page 2130
Layer 2 Interface Modes, on page 2131

Defining the Allowed VLANs on a Trunk

VLAN 1 is the default VLAN on all trunk ports in all Cisco switches, and it has previously been a requirement
that VLAN 1 always be enabled on every trunk link. You can use the VLAN 1 minimization feature to disable
VLAN 1 on any individual VLAN trunk link so that no user traffic (including spanning-tree advertisements)
is sent or received on VLAN 1.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface interface-id
4. switchport mode trunk
5. switchport trunk allowed vlan {add | all | except | remove} vlan-list
6. end
7. show interfaces interface-id switchport
8. copy running-config startup-config
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
2136
Purpose
Displays the trunk configuration of the interface.
(Optional) Saves your entries in the configuration file.