For those of you venturing into switching for the first time, one of the things that can be hard to wrap your head around if you’re just a beginner is vlans. Vlans are great ways to make the management of your network a lot more organized, and are used everywhere in this world. You’re not going to be able to enter the switching world without running into them so it’s best to learn about them asap.
Now one of the things that can cause you troubles down the road is configuring vlans across many switches in large environments. This is made easier by the use of VTP (VLAN Trunking Protocol). You can use this to automatically configure vlans across many switches.
Unfortunately you might run into a problem when using extended vlans. If you use extended vlans and VTP version 2, you will find that you can’t use vlans all the way up to 4095. Instead what you need to do is use VTP version 3 which will enable you to use the entire range, or you can put your switch in VTP transparent mode to allow it to use extended vlans.