CCNP - Vlan

[James Hoggard]

Hi,

When studying for my CCNP it talks about keeping Vlans local and this is the best design. So for example say my end switches are layer 2 2960's create the vlans here, then these uplink to my distribution switches which are layer 3. Is it saying create your SVI here and use some kind of routing protocol to route between the VLANS? why is this the best design, it is so you don't have broadcasts traversing your entire network and I'm guessing it makes it easier for troubleshooting? 

[Reza Sharifi]

Hi,

Yes, that is possible.  It is called routed access design, meaning you are routing at the access layer switches.  The draw back of that design is since the vlans are local to each each switch, you can't span a vlan across multiple switches/closets which can be a problem if you need to have 2 user on 2 different switches or closets that need to be in the same vlan. Most common practice is not to route at the access, but rather on the distribution layer.  If you have a collapsed distro/core layer, then you route at the core layer.

HTH