svi...

when configuring an svi (switched virtual interface) it is supposed to behave as when creating a loopback interface in that it doesn't have to be no shutted, it should just come up...

dsw1(config)#do sh vlan brief

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Gi0/1, Gi0/2
10   data                             active    Fa0/7, Fa0/8, Fa0/9, Fa0/10
                                                Fa0/11, Fa0/12, Fa0/13, Fa0/14
                                                Fa0/15, Fa0/16, Fa0/17, Fa0/18
                                                Fa0/20, Fa0/21, Fa0/22, Fa0/23
                                                Fa0/24
20   mgmt                             active
50   voice                             active

so we create a vlan 69 as below that has no port membership...

dsw1(config)#vlan 69
dsw1(config-vlan)#int vlan 69
dsw1(config-if)#ip add 69.69.69.69 255.255.255.0
dsw1(config-if)#end
dsw1#sh int vlan 69
Vlan69 is up, line protocol is down
  Hardware is EtherSVI, address is 000f.8ffe.0980 (bia 000f.8ffe.0980)
  Internet address is 69.69.69.69/24

but after a few moments we have...


dsw1#sh int vlan 69
Vlan69 is up, line protocol is up
  Hardware is EtherSVI, address is 000f.8ffe.0980 (bia 000f.8ffe.0980)
  Internet address is 69.69.69.69/24

 no port membership in vlan 69...

dsw1#sh vlan brie

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Gi0/1, Gi0/2
10   data                             active    Fa0/7, Fa0/8, Fa0/9, Fa0/10
                                                       Fa0/11, Fa0/12, Fa0/13, Fa0/14
                                                       Fa0/15, Fa0/16, Fa0/17, Fa0/18
                                                       Fa0/20, Fa0/21, Fa0/22, Fa0/23
                                                       Fa0/24
20   mgmt                             active
50   voice                            active
69   VLAN0069                      active


and the svi is up up...


dsw1#sh int vlan 69
Vlan69 is up, line protocol is up
  Hardware is EtherSVI, address is 000f.8ffe.0980 (bia 000f.8ffe.0980)
  Internet address is 69.69.69.69/24

a couple of things... i have read that for the svi to come up, a vlan has to be created, an ip address has to be issued, and a port needs to be assigned membership...


dsw1(config)#vlan 69
dsw1(config-vlan)#int vlan 69
dsw1(config-if)#end


dsw1#sh int vlan 69
Vlan69 is up, line protocol is down
  Hardware is EtherSVI, address is 000f.8ffe.0980 (bia 000f.8ffe.0980)


without the ip address it stands to reason that the protocol is down... so we add an ip...


dsw1(config)#int vlan 69
dsw1(config-if)#ip add 69.69.69.59 255.255.255.0
dsw1(config-if)#end
dsw1#sh int vlan 69
Vlan69 is up, line protocol is up
  Hardware is EtherSVI, address is 000f.8ffe.0980 (bia 000f.8ffe.0980)
  Internet address is 69.69.69.59/24


to get up up on an svi, create the vlan, give the svi an ip address and you're done... neither port membership nor no shut are required...