Vlan question (does vlan auto forward)

[wizkidnono]

Hi i have a question.
I haved tried googleing, i just need to send the question out.
Of course there is a catalyst manual but it is late and i have this question running around in my head.
Thought id post it here.

If i create a trunk between 3 switches (daisy chained)..
and i create Vlan 99 on sw1 and sw3.
Will switch 2 pass on the packets without having to establish vlan99 on it or do i have to do this for it to forward the packets to sw3 from sw1 ?

A'n ascii schematic

Sw1(vlan1,vlan99) -> Trunk -> Sw2 (vlan1) -> trunk sw3(vlan1,vlan99)

Will Sw1(vlan99) be passed on to Sw3(vlan99) if sw2 has not created vlan99 ?

Best regards

Wizkidnono

 

[wizkidnono]

The Vlans by the way are created with

conf term
interface Gi0/24
switchport mode trunk

 

[wizkidnono]

Oh man I am to tired to make the post right.
Well third try

The trunks are created that way, the vlans are created manualy with conf term as well

 

[zinkann]

In order to pass your vlans to all of the switches, you will need to use this command on all 3 trunk ports....
"switchport trunk allow vlan 1,99"

"switchport access vlan 99" will allow, lets say a PC, to access vlan 99 on a designated port.


CCNA, Network+

 

[burtsbees]

Basshead, that command will allow ONLY 1 and 99 to pass along the trunks. All VLANs by default can be advertised...

The information will be known by all three if they are in the same VTP domain, if they have the same VTP password, and use the same VTP version, and one switch with the VLAN info is configured as VTP server, and the other two are configured as VTP clients (NOT transparent or server). The answer is VTP.
Of course, they must be VTP capable (like 2900 series...I prefer the 2950).

Burt

 

[vipergg]

Depends on if you are running client/server or transparent mode. If tranparent mode on all switches then you have to manually configure all layer 2 vlans on each switch then allow whatever vlans are needed across those trunks.