Vlan Config

[bkaren1278]

I have 2 catalyst 4507s. I have configured one as a VTP server. I have 3 VLANs.

VLAN 1 = 10.0.0.x

Vlan 2 = 192.168.1.0

Vlan 3 = 192.168.2.0

I have done the following

(conf)vlan 1

int vlan 1

ip address 10.0.0.1

then

vlan 2

int vlan 2

no ip address

then

vlan 3

int vlan 3

no ip address

i have not assigned any ports to the vlans yet so everything by default is in vlan1.

My question is this, on my 2nd switch do i have to go through the same process again and go and replicate the

vlan 2

int vlan 2

no ip address

????

[Prashanth Krishnappa]

VTP will only propogate VLAN database. The actual SVI(layer 3 VLAN interfaces) need to be created depending on how you want to route VLANs. In anycase, you will need atleast one VLAN interface for management purpose.

[bkaren1278]

heres a stupid question, what is the point of a vlan database?

also, how come we have to add the layer 3 vlan int to the vlan already in the db (i.e. vlan 2, int vlan 2, while in config) ?

[alaporte]

VTP is a Layer 2 messaging protocol that maintains VLAN configuration consistency by managing the addition, deletion, and renaming of VLANs on a network-wide basis. VTP minimizes misconfigurations and configuration inconsistencies that can result in a number of problems, such as duplicate VLAN names, incorrect VLAN-type specifications, and security violations. See… http://www.cisco.com/univercd/cc/td/doc/product/lan/cat5000/rel_4_2/config/vlans.htm

I do not know of one that works for layer 3 or why you would even consider one.

As for what good is VTP, its not much if you only have 2 switches but when you have something like 5+ switches that all need the same VLAN inforation (layer 2) why would you want to configure all the different VLAN on the switches when VTP will put it there for you.

Andy

[bkaren1278]

thanks for the great explanation though i think i still have a few questions.

correct me if i am wrong here.

to create a layer 2 vlan i simply go to the config terminal and type vlan 2 or so and then i go ahead and assign the ports with switchport access vlan 2. Now i would use layer 2 vlan to cut the broadcasts down by grouping ports together. I can do for example a marketing workstation vlan. But if the marketing vlan needs to get to the server vlan, even if theyre on the same subnet i will need to use layer 3? i would do this by adding "int vlan x" ???

i think this is where i am confused, please help me clarify this fundemental principal

[glen.grant]

You generally have one vlan per subnet and that is how it is broken up when configuring . The server vlan will be one address range and the marketing vlan will be another layer 3 subnet .