Vlans and IP addresses

[Jim Yorke]

New to networking and am trying to understand something.  I have a switch on vlan 10 and I setup a trunk port to configure a new switch that will be on vlan 30.  How do I configure my vlan 10 switch so that it will see vlan 30 as well as the new switch?  I have the interface vlan30 created but am confused on whether or not it needs an ip address to connect to vlan 30 or as to where I would get that ip address.

[Flavio Miranda · Accepted solution]

Hi @Jim Yorke 

 This is a very interesting question as it mix up two concept very often people gets confuse.

- One vlan can not communicate with another different vlan, on the same switch or in a different switch. Dont matter if you have IP address or trunk between switch.

Vlans are layer2 broadcast domain and in order to allow two differents vlans to communicate, you need to use a layer3 device or a switch with layer3 feature.

In your case, what you can do is enable ip routing on the switch, if the switch support it , and add IP address on both vlans.

Another alternative, in case the switch does not support ip routing, is to use a Router to route between vlan.