Which command do you enter to verify that a VLAN has been removed from a trunk?

6 thoughts on “Which command do you enter to verify that a VLAN has been removed from a trunk?”

1. none of the answers are correct.

   Switch(config-if)# switchport trunk allowed vlan vlan_list will show list of allowed vlans on a trunk, from which we can verify if a vlan has been removed.

   Reference :
   switchport trunk allowed vlan {{ add | except | remove } vlan_list | all | none }

   add :Specifies the VLANs to be added to the current list.
   except :Specifies all VLANs to be added to the current list, except the specified VLANs.
   remove:Specifies the VLANs to be removed from the current list.

   vlan_list : VLAN IDs of the allowed VLANs when the interface is in trunking mode. The range is from 1 to 4094, except for the VLANs reserved for internal use.
   Use a hyphen (-) to separate the beginning and ending IDs of a range of VLAN IDs; for example, 70-100.
   Use a comma (,) to separate individual VLAN IDs and ranges of VLAN IDs; for example, 20,70-100,142.

   all : Specifies all VLANs to be added to the current list.
   none: Specifies that no VLANs be added to the current list.

   https://www.cisco.com/c/m/en_us/techdoc/dc/reference/cli/nxos/commands/l2/switchport-trunk-allowed-vlan.html

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   1. correct command should be
      Switch(config-if)# switchport trunk allowed vlan vlan_list.

      where vlan_list : VLAN IDs of the allowed VLANs when the interface is in trunking mode. The range is from 1 to 4094, except for the VLANs reserved for internal use.

      option A ( Switch(config-if)# switchport trunk allowed vlan none) is incorrect since
      none: Specifies that no VLANs be added to the current list.

      Reply

2. Answer A is correct because there is no command like the option B and C.

   The correct command is:(config-if)#switchport trunk allowed vlan remove

   OR

   (config-if)#switchport trunk allowed vlan except

   Checked on Packet Tracer!!

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3. Switch(config-if)#switchport trunk allowed vlan ?
   WORD VLAN IDs of the allowed VLANs when this port is in trunking mode
   add add VLANs to the current list
   all all VLANs
   except all VLANs except the following
   none no VLANs
   remove remove VLANs from the current list

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4. It’s only answer A because the “switchport trunk remove vlan 10” doesn’t exist.
   the good command to remove only one vlan is
   Switch(config-if)#switchport trunk allowed vlan remove X

   For D it’s only ; Switch(config-if)#no switchport trunk allowed vlan 5

   So the good answer is A.

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5. Answer A makes sure the list of allowed VLANS is empty (except for the VLAN 1 which cannot be removed).

   The question asks how to Verify. This is usually done with a #show command, like #show interface trunk
   But this is not one of the possible answers. So the question should probably be something like:

   Which command do you enter to remove a VLAN from a trunk?
   –> Answer C

   Reply