topic VLAN Trunking in Switches, Hubs, and Modems

VLAN Trunking

Justin Parker — Wed, 16 Aug 2006 10:05:51 GMT

I wonder if anyone can help me with this scenario...
I have a 2 x 2626 switches.
Switch1 is configured as;
Ports 1-8 VLAN1 (Static)
Ports 9-24 VLAN2 (Static)

Switch2 is configured as;
Ports 1-8 VLAN1 (Static)
Ports 9-24 VLAN2 (Static)

Port 25 on Switch1 is connected to Port 25 on Switch 2 over a 1000mg fibre link.

I would like to "trunk" (if this is the right terminology) VLAN1 and VLAN2 over this fibre link.
However I do not want any routing to occurr between the two VLANS.
The reading I have done so far seems to indicate that I will need to Tag the VLANS and then trunk them over the fibre link.
I suspect I may be confusing a couple of different concepts however.

Any ideas appreciated.

Re: VLAN Trunking

Mohieddin Kharnoub — Wed, 16 Aug 2006 10:18:35 GMT

Hi

In fact what you want exactly is called Tagging not Trunking.

Port trunking allows you to assign physical links to one logical link (trunk)that functions as a single, higher-speed link.

So if you want to make both ports 25 and 26 to be Ony logical link, thats what they call it Trunk.

What you need is to Tag Vlan2 only on port 25 on both switches:

2626(config)# vlan 2 tag 25
2626(config)# write mem

Repeat same commands on the second switch.
Vlan 1 is untagged by default on all ports, so both vlans traffic will be carried on the link between 25 port on both switches.

Don;t forget to assing points.

Good Luck !!!

Re: VLAN Trunking

Mohieddin Kharnoub — Wed, 16 Aug 2006 10:49:56 GMT

More info. about Vlans - Trunking:
ftp://ftp.hp.com/pub/networking/software/AdvTraff-Oct2005-59908853-Chap02-VLAN.pdf

Re: VLAN Trunking

Justin Parker — Thu, 17 Aug 2006 04:28:04 GMT

Thanks Guys - That did the job!

Re: VLAN Trunking

velislav veliov — Tue, 10 Jul 2007 11:48:34 GMT

Once the physical link carying both vlans is created as suggested will broadcast traffic still be isolated btw the vlans? i have setup my physical link as described above however my vlan 1 clients are obtaining vlan2 dhcp addresses. Any suggestions?