Vlans allowed and active in management domain

[robertmprsoman]

Greetings everyone, so I have 2 port channels configured with trunk ports on my core switch in packet tracer. I allow Vlan 10 on these port channels but I run the "Show int trunk" command I realized that "Vlans allowed and active in management domain" lists as "none. I believe as a result vlan 10 is not being traversed across  See script below:

Port Mode Encapsulation Status Native vlan

Po1 on 802.1q trunking 1

Po2 on 802.1q trunking 1

Port Vlans allowed on trunk

Po1 10

Po2 10

Port Vlans allowed and active in management domain

Po1 none

Po2 none

Port Vlans in spanning tree forwarding state and not pruned

Po1 none

Po2 none

[M02@rt37]

Hello @robertmprsoman,

The "Port Vlans allowed on trunk" section indicates that VLAN 10 is allowed on the trunks Po1 and Po2. The "Port Vlans allowed and active in management domain" section is not directly related to VLAN 10's traversal.

In Cisco switches, the "Vlans allowed and active in management domain" field typically lists the VLANs that are currently active and allowed on the trunk link within the VTP domain. This field might be related to VTP pruning, which is a mechanism that helps to optimize bandwidth usage by allowing only necessary VLANs to pass over trunk links.

If you're seeing "none" in the "Vlans allowed and active in management domain" field, it might indicate that there are no VLANs currently active and allowed on the trunk link within the specified VTP domain. However, this might not directly affect VLAN 10's traversal, especially if you're seeing that VLAN 10 is allowed on the trunks Po1 and Po2.

Plus, you're using Packet Tracer, then it's possible that certain features or behaviors might differ from real networking equipment.

[Aladdin0z]

Hello @robertmprsoman  

Can you share the output of the command 

# show spanning-tree vlan 10

you will see if the channels are acctuely in the FWD status .