Layer 3 vlans up up

[Jonathancert_2]

I am way behind the times when it comes to layer three switching.  I didn't have a problem doing inter-vlan routing but recently i was configuring a C4900M with a VLAN and noticed that the VLAN would not come up unless a device was connected the the applied ports of the VLAN.  For example, if I made at:

(config)# Inter VLAN 400

until i applied it to a interface

(config-if)#switchport access vlan 400

and an active broadcasting device to the port, the VLAN is down hard.

Is this normal?

P.S.  The C4900M is in transparent mode and the managment VLAN is the only VLAN being trunked to my 6509

[Lei Tian · Accepted solution]

Hi,

That is normal, SVI will not come up unless you have active instance for that VLAN.

HTH,

Lei Tian

[Jonathancert_2]

Thanks.  That would explain why when I add VLAN 400 to my trunking interface it comes up.