VLAN interface down

[sdross]

What is the minimum configuration for setting up two ports in their own vlan? I ask because when I "sh vlan bri" I see vlan 2 active and the two ports that I want are members however I cannot get the interface to come up. When I "no shut" vlan 2, it still says that it is shutdown. This is on a 2900 LRE XL switch.

Thanks for any help.

[Prashanth Krishnappa]

On a XL switch, you can have only one L3 VLAN interface up/up

http://www.cisco.com/warp/customer/473/8.html#topic4

It's a L2 switch only and no value in having more than one VLAN interface up/up

[rjackson]

Sounds like you have not created the vlan. Two steps. Create the vlan in the vlan database then assign ports to it. You can assign ports to non existing vlans but they wont work.

You do not create it with int vlan statement.

[sdross]

This is just a question, please don't take it the wrong way. If the vlan was not created, wouldn't it be missing or not show up when you do a show vlan brief?

Your right, I didn't create the vlan, someone else had already done it. Thats why I was wondering if they had not finished the configuration.

[rjackson]

I dont know without testing. I just remember beating my head for several hours trying to bring up ports that I put into a new vlan. The config showed the interfaces were in the vlan but they wouldn't come up until I remembered to create the vlan.

Try putting a port in a new vlan and do show vlan and see.

[rajesh444]

I have a related question.

While I noticed that on the Cat.2948G, when a switch port is assigned to a non-existent VLAN it goes into "inactive" state but on the Cat.2950 when the same thing is done, the switch recognizes that the VLAN does not exist & automatically creates the new VLAN which shows up as active when a "show vlan" is performed.

Is this feature IOS release or platform dependent?

Any help would be greatly appreciated.

Thanks,

RAJ

[andrew.butterworth]

The 2900XL (& 3500XL) switches are purely layer-2 devices. The VLAN interface in the configuration is the Management interface of the switch; by default this is VLAN1, if you move all the ports on the switch to another VLAN then the switch won't be reachable over the network - i.e. you won't be able to telnet to it. I assume you are attempting to split up the ports on the switch into different VLANs (switchport access vlan xxx). You are doing this the right way but the VLAN's must be created in the VLAN database, NOT in config mode. From the CLI type 'vlan database', from here you can add and delete VLAN's. Once the VLAN exists you can put ports in different VLAN's from config mode (switchport access vlan xxx).

When you show the config (show running-config) there will always be a VLAN 1 interface, if this isn't the VLAN you will be managing the switch by then it will be shutdown and another VLAN interface will exist in the config.

Andy

[kpahare]

Hi

The vlan will be in shut down mode unless u assign an ip address to it. i've 2924 xl-v switch and all the ports are assign to vlan 2 and working fine, but the output of show vlan bri shows "vlan 2 shutdown".

kin

[sdross]

So you as long as the two ports that I want are in vlan 2, they might still communicate and work with vlan 2 showing "shutdown"and without an ip address on vlan 2, is this right?

[milan.kulik · Accepted solution]

Yes,

as far as two ports are in VLAN2 they can communicate each to the other.

"VLAN2 shutdown" is showing the INTERFACE named "VLAN2" status.

(You can see it via show int command, not via show vlan command.)

This interface could be used for the switch management if you wanted to manage it (Telnet to it, e.g.) from a management station situated in VLAN2.

But you would have to shutdown interface VLAN1 first and do "no shut" command in interface VLAN2 config.

I know it's confusing that VLAN2 means a management interface in one context and it means a real VLAN in other context but this is the way Cisco works. "Integrface VLANx" status has nothing to do with VLANx (i.e. VLAN number x) capability to connect two devices.

Regards,

Milan

[sdross]

Exactly what I was looking for!

Thanks