I am using a C2950-24 as a bit of practice for the CCNA exams, a snag I hit is that I can create multiple VLANs but when I enable one with the no shutdown command and previously enabled VLAN goes down.
Does anyone know if this is a limitation with the switch or maybe the version of IOS I'm using? "Version 12.1(6)EA2c, RELEASE SOFTWARE(fc1)" Btw
Any feedback would be appreciated.
Vlans are layer 2. By assigning an interface to them they don't become layer 3, it just means that you can now route between vlans if you need to.
You can't have a L3 vlan interface without the layer 2 vlan existing but the reverse is not true. In most networks there is usually a direct correlation between a L2 vlan and a L3 vlan interface but you could quite easily just create a L2 vlan only. Any machines connected into this vlan would only be able to talk to each other within the vlan.
Hope that makes things clearer ?