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Catalyst 3560 Switch Software Configuration Guide
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Chapter 12 Configuring VLANs
Configuring VLAN Trunks
To return to the default pruning-eligible list of all VLANs, use the no switchport trunk pruning vlan
interface configuration command.
Configuring the Native VLAN for Untagged Traffic
A trunk port configured with 802.1Q tagging can receive both tagged and untagged traffic. By default,
the switch forwards untagged traffic in the native VLAN configured for the port. The native VLAN is
VLAN 1 by default.
Note
The native VLAN can be assigned any VLAN ID.
For information about 802.1Q configuration issues, see the
“802.1Q Configuration Considerations”
section on page 12-18
.
Beginning in privileged EXEC mode, follow these steps to configure the native VLAN on an 802.1Q
trunk:
Step 3
switchport trunk pruning vlan {add |
except | none | remove} vlan-list
[,vlan[,vlan[,,,]]
Configure the list of VLANs allowed to be pruned from the trunk. (See
the
“VTP Pruning” section on page 13-4
).
For explanations about using the add, except, none, and remove
keywords, refer to the command reference for this release.
Separate nonconsecutive VLAN IDs with a comma and no spaces; use a
hyphen to designate a range of IDs. Valid IDs are from 2 to 1001.
Extended-range VLANs (VLAN IDs 1006 to 4094) cannot be pruned.
VLANs that are pruning-ineligible receive flooded traffic.
The default list of VLANs allowed to be pruned contains VLANs 2 to
1001.
Step 4
end
Return to privileged EXEC mode.
Step 5
show interfaces interface-id switchport Verify your entries in the Pruning VLANs Enabled field of the display.
Step 6
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Command
Purpose
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
interface interface-id
Enter interface configuration mode, and define the interface that is
configured as the 802.1Q trunk.
Step 3
switchport trunk native vlan vlan-id
Configure the VLAN that is sending and receiving untagged traffic
on the trunk port.
For vlan-id, the range is 1 to 4094.
Step 4
end
Return to privileged EXEC mode.
Step 5
show interfaces interface-id switchport
Verify your entries in the Trunking Native Mode VLAN field.
Step 6
copy running-config startup-config
(Optional) Save your entries in the configuration file.