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Problem with vlan on the switch

Good morning ladies,

I have a Model 2950 Switch Catalysts and would like to segment it into three VLANs created the vlans vlan 2 and 3 and added the ports to their fast ethernet vlans but when I type the command on shutdown in interface vlan1 interface rises co momo up normal but if it is in VLAN2 and enter the command no shutdown interface VLAN2 rises up and as vlan1 interface becomes down, and vice versa. what can it be? I thank you to attention!

15 Replies 15

Ganesh Hariharan
VIP Alumni
VIP Alumni

Good morning ladies,

I have a Model 2950 Switch Catalysts and would like to segment it into three VLANs created the vlans vlan 2 and 3 and added the ports to their fast ethernet vlans but when I type the command on shutdown in interface vlan1 interface rises co momo up normal but if it is in VLAN2 and enter the command no shutdown interface VLAN2 rises up and as vlan1 interface becomes down, and vice versa. what can it be? I thank you to attention!

Hi,

Since its a 2950 L2 switch you cant have more than one SVI, it will automatically shut the existing SVI interface if you configure a new one.

Hope to help !!

Ganesh.H

Remember to rate the helpful post

Good morning ladies,

I did not understand very well the friend's answer above!
I would like to better understand this problem!

Tiago Eduardo Zacarias

Good morning ladies,

I did not understand very well the friend's answer above!
I would like to better understand this problem!

Tiago Eduardo Zacarias

2950 is a Layer 2 switch, it does not support Inter-vlan routing and can only have one vlan interface active for Management purpose.so what you are seeing is a normal behaviour of the switch.It can have only one SVI for management purpose and for troubleshooting purpose in future If the Layer 2 VLAN is not created on the switch,SVI interfaces show as UP/DOWN in the show ip interface brief command output when the configuration is applied to the switch.

Hope to help !!

Ganesh.H

Hi Ganesh,

Congratulations on your new blue badge

Reza

Hi Ganesh,

Congratulations on your new blue badge

Reza

Thanks Reza !!

Ganesh.H

ladies,?????

Giuseppe Larosa
Hall of Fame
Hall of Fame

Hello Tiago,

>> what can it be?

L2 only switch: I tested this some years ago. only one active SVI is supported on C2950 as soon as you attempt to enable SVI vlan Y  SVI vlan X is shutted down.

Hope to help

Giuseppe

Hello Giuslar,

Then there is no way around it not? how could proceed to resolve this problem or there is no solution?

  You are attempting to route between those vlans with a layer 2 only switch , will not work .  You will need to trunk the 2950 to a router  or a layer2/3 switch which will do intervlan routing.   The answer is buy a router or a layer2/3 switch to do the routing .

Good Morning Glen

In my case I have no need for routeamento between the VLANs and create segment as DMZ, WAN the same switch! understand?! But what the solution would also know this case is the same interface vlan down the interfaces would be separated from other interfaces and vlans.

Tiago Eduardo Zacarias

On a 2950 switch, you can create the three VLANs that you want to have active.  Since the 2950 is a Layer 2 device, it can only have one IP Address assigned to a VLAN interface, and only one VLAN can be 'Up' at any one time.  If VLAN1 has an IP Address assigned to it (you would use this IP to Telnet to it, etc) and you try to bring up VLAN2, VLAN1 will shut down, since only one VLAN can be active at one time.

So, what you need to do is assign your management/Telnet IP Address to the correct VLAN.  Then assign the correct switchports to the correct VLAN.  Do not attempt to bring any Vlan interfaces up, just your switchport interfaces Fa0/1-24.  Makes sense?

Leo Laohoo
Hall of Fame
Hall of Fame

Like what everyone said, the 2950, like the 2900XL/3500XL and 2940, will only allow one active management VLAN at any time.  Remember that VLAN IP address is used primarily for (remote) management purposes.  It doesn't affect any of your Layer 2 traffic.

What are you trying to do?  You created three VLANs.  Do you want each VLANs to communicate to each other?  If so, Glenn is correct.  If you have only the 2950 switch and no other layer 3 device(s) then it won't work because the 2950 will not support layer 3 routing.

Configuring EtherChannel and 802.1Q Trunking Between Catalyst L2 Fixed Configuration Switches and a Router (InterVLAN Routing)
http://www.cisco.com/en/US/customer/products/hw/switches/ps628/products_configuration_example09186a00800ef797.shtml

Configuring InterVLAN Routing with Catalyst 3750/3560/3550 Series Switches
http://www.cisco.com/en/US/customer/tech/tk389/tk815/technologies_configuration_example09186a008015f17a.shtml

Good Evening Gentlemen,

I reached a conclusion that I can I switch my target and raise only one vlan remote management of the character as the friend above said This capability was my doubts as I am new to the area thought that with the other VLANs would be trouble down the communication segment. Mias as colleagues up there said that there is no problems then I'm quiet! ok Thank you all! only one question from which I can switch all vlan up for standalone management?

Tiago Eduardo Zacarias

Que???

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