mac
VLAN Configuration
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Switch(Config-If-Ethernet1/8)#exit
Switch(config)#interface ethernet 1/10
Switch(Config-If-Ethernet1/10)#switchport mode hybrid
Switch(Config-If-Ethernet1/10)#exit
15.1.35 switchport mode trunk allow-null
Command: switchport mode trunk allow-null
Function: Add a port as trunk mode. When enabling GVRP, the mode that adds the
ports with trunk mode to all VLANs is not appropriate. Therefore, add a port as trunk port
and does not join any VLANs by default for enabling GVRP on trunk port is appropriate.
It is recommended to configure a port as trunk with this command before enabling GVRP.
This command can also be used when a port has been configured as trunk already,
which equals to clearing allow-list and quits all VLANs.
Parameters: None
Command Mode: Port mode
Default: access mode.
Usage Guide: Configure the port as trunk, enable it to leave all VLANs and clear
allow-list.
Example: Switch(config-if-ethernet1/1)#switchport mode trunk allow-null
15.1.36 switchport trunk allowed vlan
Command: switchport trunk allowed vlan {WORD | all | add WORD | except WORD
| remove WORD}
no switchport trunk allowed vlan
Function: Set trunk port to allow VLAN traffic; the “no switchport trunk allowed vlan”
command restores the default setting.
Parameter: WORD: specified VIDs; keyword;
all: all VIDs, the range from 1 to 4094;
add: add assigned VIDs behind allow vlan;
except: all VID add to allow vlan except assigned VIDs;
remove: delete assigned allow vlan from allow vlan list.
Command mode: Port Mode.
Default: Trunk port allows all VLAN traffic by default.
Usage Guide: The user can use this command to set the VLAN traffic allowed to
passthrough the Trunk port; traffic of VLANs not included are prohibited.
Example: Set Trunk port to allow traffic of VLAN1, 3, 5-20.
Switch(config)#interface ethernet 1/5










