why vlan line protocol is down ?

Unanswered Question
Apr 11th, 2009

plz check this one & tell me why line protocol is down

I have this problem too.
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pciaccio Sat, 04/11/2009 - 19:10

Your VLAN 1 is UP/DOWN because out of the whole configuration on the file you attached your VLAN 1 is not up on any interface in the switch. All your UP interfaces have VLANs 100,200,300 on them only. VLAN 1 is not on any up interface... Allow VLAN 1 on any of the UP interfaces and it will come UP/UP for you...Good Luck...

Giuseppe Larosa Sun, 04/12/2009 - 02:59

Hello Kaustubh,

an SVI is a logical interface but it is up/up only if at least one L2 interface (access or trunk) is in STP forwarding state.

This is called autostate.

As other collegues have noted you have no live interface on L2 broadcast domain vlan1 and so L3 interface Vlan1 is up/down.

Hope to help


lamav Sun, 04/12/2009 - 08:28


Here is a link to what everyone is taking about:


Take note, I wouldnt recommend using vlan 1 as a regular vlan in which to place hosts, servers, etc. Vlan 1 is used by Cisco switches to pass control plane traffic and should remain untouched as a best practice.

If its not your intention to use vlan 1 to route traffic from hosts you place in it, then you dont need the SVI and it should be removed. Then you wont have to worry about it coming up...




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