Configuring VLAN Trunks
Configuring an Ethernet Interface as a Trunk Port
Configuring a Trunk Port
Because trunk ports send and receive VTP advertisements, to use VTP you must ensure that at least one trunk
port is configured on the switch and that this trunk port is connected to the trunk port of a second switch.
Otherwise, the switch cannot receive any VTP advertisements.
Before You Begin
SUMMARY STEPS
1. configure terminal
2. interface interface-id
3. switchport mode {dynamic {auto | desirable} | trunk}
4. switchport access vlan vlan-id
5. switchport trunk native vlan vlan-id
6. end
7. show interfaces interface-id switchport
8. show interfaces interface-id trunk
9. copy running-config startup-config
DETAILED STEPS
Command or Action
Step 1
configure terminal
Example:
Switch# configure terminal
Step 2
interface interface-id
Example:
Switch(config)# interface
gigabitethernet1/0/2
Step 3
switchport mode {dynamic {auto | desirable} |
trunk}
Example:
Switch(config-if)# switchport mode dynamic
desirable
OL-29065
Purpose
Enters the global configuration mode.
Specifies the port to be configured for trunking, and enters
interface configuration mode.
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.
Catalyst 2960-X Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX
Configuring an Ethernet Interface as a Trunk Port
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