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Cisco IE 2000 Switch Software Configuration Guide
OL-25866-01
Chapter 17 Configuring VLANs
How to Configure VLANs
Configuring an Ethernet Interface as a Trunk Port

Defining the Allowed VLANs on a Trunk

Changing the Pruning-Eligible List

Command Purpose
Step 1 configure terminal Enters global configuration mode.
Step 2 interface interface-id Specifies the port to be configured for trunking, and enters interface
configuration mode.
Step 3 switchport mode {dynamic {auto |
desirable} | trunk}
Configures the interface as a Layer 2 trunk (required only if the interface
is a Layer 2 access port or tunnel port or to specify the trunking mode).
dynamic auto—Sets the interface to a trunk link if the neighboring
interface is set to trunk or desirable mode. This is the default.
dynamic desirable—Sets the interface to a trunk link if the
neighboring interface is set to trunk, desirable, or auto mode.
trunk—Sets the interface in permanent trunking mode and negotiate
to convert the link to a trunk link even if the neighboring interface is
not a trunk interface.
Step 4 switchport access vlan vlan-id (Optional) Specifies the default VLAN, which is used if the interface
stops trunking.
Step 5 switchport trunk native vlan vlan-id Specifies the native VLAN for IEEE 802.1Q trunks.
Step 6 end Returns to privileged EXEC mode.
Command Purpose
Step 1 configure terminal Enters global configuration mode.
Step 2 interface interface-id Specifies the port to be configured, and enters interface configuration
mode.
Step 3 switchport mode trunk Configures the interface as a VLAN trunk port.
Step 4 switchport trunk allowed vlan {add |
all | except | remove} vlan-list
(Optional) Configures the list of VLANs allowed on the trunk.
Step 5 end Returns to privileged EXEC mode.
Command Purpose
Step 1 configure terminal Enters global configuration mode.
Step 2 interface interface-id Selects the trunk port for which VLANs should be pruned, and enters
interface configuration mode.