07-30-2007 03:48 PM - edited 03-05-2019 05:35 PM
I have a 3550 switch that I am trying to set up a trunk port and only trunk two VLANs.
When I try to remove all VLANs other than what I want, I get this message:
"Command rejected: Bad VLAN allowed list.
VLANs 1,1002-1005 are required."
Do I have to allow these VLANs?
07-30-2007 04:21 PM
Yes. You can never disallow vlans 1002 through 1005. Those are native to the IOS.
All you have to do is type "switchport trunk allowed vlan x,y,z"
The rest will be pruned by default.
07-30-2007 04:56 PM
thanks everyone
07-30-2007 04:22 PM
Wilson,
Those are default VLANs that you couldn't remove in the past. But the newer IOS lets you remove the default VLANs from the trunk. Here's a small capture from my lab switch.
SW1-3550#show run int f0/24
Building configuration...
Current configuration : 154 bytes
!
interface FastEthernet0/24
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 100
switchport mode trunk
switchport nonegotiate
end
SW1-3550#show int trunk
Port Mode Encapsulation Status Native vlan
Fa0/24 on 802.1q trunking 1
Port Vlans allowed on trunk
Fa0/24 100
Port Vlans allowed and active in management domain
Fa0/24 100
Port Vlans in spanning tree forwarding state and not pruned
Fa0/24 100
HTH
Sundar
07-30-2007 04:33 PM
Sundar, you can prune those vlans by default by not including them in the 'allowed vlan' statement. Correct?
07-30-2007 04:34 PM
Correct.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide