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New Member

VLAN interface is up and strange VTP issue

Hi

I have two problems with a 2950 switch that I think might be related, just a hunch. The switch is connected to our core Cisco network over a dot1q trunk carrying some 20 VLANs. One of these VLANS is our admin network, VLAN 10, that the switch has a VLAN interface assigned to it.

Now, the troubling thing is that in our network I have a VTP domain set up that isn't propagated to the 2950 switch. As a test I disconnected the network cable connecting the 2950 to our core and to my surprize the VLAN 10 interface remained up. The switch logged that the physical interface went down but never the VLAN interface.

No VTP is annoying but the VLAN interface remaining up is just strange.

Any ideas?

/Fredrik

  • LAN Switching and Routing
3 REPLIES
Purple

VLAN interface is up and strange VTP issue

Hi,

having a trunk interface with that vlan allowed and which is forwarding for this vlan in STP is enough to have the SVI up.

Regards

Alain

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New Member

VLAN interface is up and strange VTP issue

Yes, having a trunk with VLAN for the interface should be enough. The SVI is up but never goes down when the trunk is disconnected.

Purple

VLAN interface is up and strange VTP issue

Hi,

are there other ports in vlan 10 in STP forwarding state ? if so that's why the SVI stays up.

sh spanning-tree vlan 10 output will tell you.

Regards

Alain

Don't forget to rate helpful posts.

Don't forget to rate helpful posts.
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