Switchport Mode - Cisco Catalyst 3550 Command Reference Manual

Chapter 2 Cisco IOS Commands

switchport mode

Use the switchport mode interface configuration command to configure the VLAN membership mode
of a port. Use the no form of this command to reset the mode to the appropriate default for the device.
Syntax Description
access
dot1q-tunnel
dynamic auto
dynamic desirable
trunk
Defaults
The default mode is dynamic desirable.
Command Modes Interface configuration
Command History Release
12.1(4)EA1
12.1(9)EA1
Usage Guidelines
A configuration that uses the access, trunk, or dot1q-tunnel keywords takes effect only when you
configure the port in the appropriate mode by using the switchport mode command. The static-access
and trunk configuration are saved, but only one configuration is active at a time.
When you enter access mode, the interface changes to permanent nontrunking mode and negotiates to
convert the link into a nontrunk link even if the neighboring interface does not agree to the change.
When you enter trunk mode, the interface changes to permanent trunking mode and negotiates to
convert the link into a trunk link even if the interface connecting to it does not agree to the change.
When you enter dynamic auto mode, the interface converts the link to a trunk link if the neighboring
interface is set to trunk or desirable mode.
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switchport mode {access | dot1q-tunnel | dynamic {auto | desirable} | trunk}
no switchport mode {access| dot1q-tunnel | dynamic {auto | desirable} | trunk}
Set the port to access mode (either static-access or dynamic-access depending
on the setting of the switchport access vlan interface configuration command).
The port is set to access unconditionally and operates as a nontrunking, single
VLAN interface that sends and receives nonencapsulated (non-tagged) frames.
An access port can be assigned to only one VLAN.
Set the port as an 802.1Q tunnel port.
Set the interface trunking mode dynamic parameter to auto to specify that the
interface convert the link to a trunk link.
Set the interface trunking mode dynamic parameter to desirable to specify that
the interface actively attempt to convert the link to a trunk link.
Set the port to trunk unconditionally. The port is a trunking VLAN Layer-2
interface. The port sends and receives encapsulated (tagged) frames that
identify the VLAN of origination. A trunk is a point-to-point link between two
switches or between a switch and a router.
Modification
This command was first introduced.
The dot1q-tunnel keyword was added.
Catalyst 3550 Multilayer Switch Command Reference
switchport mode
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