vlan question

I'm having some trouble setting up vlans on my switches and I'm not 100% sure why... I have 3 2950 switches, with switch 1 being the vtp server and 2 & 3 being clients. When I bring vlan 2 up on switch 2 or 3, I get this message:

Switch2(config-if)#int vlan 1
Switch2(config-if)#no shut
Switch2(config-if)#
02:16:29: %LINK-3-UPDOWN: Interface Vlan1, changed state to up
Switch2(config-if)#
02:16:29: %LINK-5-CHANGED: Interface Vlan2, changed state to administratively down
02:16:30: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up
02:16:30: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan2, changed state to down
Switch2(config-if)#

So basically, I bring vlan 2 up and it shuts vlan 1 down and then when I bring vlan 1 up it shuts down vlan 2. I'm confused

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Comments

networker050184

I think your confusion comes from not knowing the difference between a VLAN and an SVI. You aren't actually shutting/no shutting the VLAN itself. On a 2950 you can only have one SVI up at a time. This is used only for management of the switch.

Greenmet29

Do you know why on switch one the vlan would show act/lshut?

Switch1#show vlan br

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Fa0/1, Fa0/2, Fa0/3, Fa0/4
                                                Fa0/5, Fa0/6, Fa0/7, Fa0/8
                                                Fa0/9, Fa0/10, Fa0/12, Fa0/13
                                                Fa0/14, Fa0/15, Fa0/16, Fa0/17
                                                Fa0/18, Fa0/19, Fa0/20, Fa0/21
                                                Fa0/22, Fa0/24, Gi0/1, Gi0/2
2    L-vlan                      act/lshut Fa0/11
3    VLAN0003                         active
4    K-vlan                     active
1002 fddi-default                     act/unsup
1003 trcrf-default                    act/unsup
1004 fddinet-default                  act/unsup
1005 trbrf-default                    act/unsup

And the fa0/11 int on switch1 is orange, but when I put it back in vlan1 it goes green

networker050184

That is if you shutdown the VLAN itself.

configure terminal
vlan 2
shutdown

Which is different than shutting down an SVI.

configure terminal
interface vlan 2 
shutdown

Greenmet29

Ahhhhhhhhhhhh.... nice.. so I think I understand now. I got that before but now I guess I just got confused about it. I think it's because i'm just used to typing "int" before it. I have to remember that the actual vlan isn't an interface, but that you can have an interface a vlan, but only one per switch. This is in order to have telnet/ssh access to the switch, right?

networker050184

Greenmet29 wrote: »

Ahhhhhhhhhhhh.... nice.. so I think I understand now. I got that before but now I guess I just got confused about it. I think it's because i'm just used to typing "int" before it. I have to remember that the actual vlan isn't an interface, but that you can have an interface a vlan, but only one per switch. This is in order to have telnet/ssh access to the switch, right?

Correct. Unless the switch is L3 it can have multiple SVIs up for routing between them. Think of the SVIs as the subinterfaces if you were doing ROAS with an external router.

Greenmet29

Sweet! Thanks for your help!