1) vlan in global config mode creates the vlan at layer 2. You can create multiple vlans at layer 2 on the 2960 switch and you can then allocate ports into these vlans.
2) int vlan 20
this does not create a L2 vlan. It creates a L3 vlan interface or SVI (Switched Virtual Interface). To route between vlans you need L3 vlan interfaces. The 2960 is a L2 switch only so you can only create 1 L3 vlan interface and this interface is used so you can remotely connect to the switch.
A L3 switch such as the 3560/3750/4500/6500 can have multiple L3 vlan interfaces.
So L2 switch can have multiple L2 vlans + 1 L3 vlan interface.
L3 switch can have multiple L2 vlans + multiple L3 vlan interfaces.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.