VLAN n00b needs help

Sone · 28 Jul 2006 at 10:08

Setup a few vlans in the past but allways on the same switch / stack.

If i want to extend this across the network how would i go about doing this, i assume it muct have something to do with tagging packets? (i am probably misunderstanding but is it as simple as setting up uplinks on there own vlan and enable tagging for these ports?)

markwombat · 28 Jul 2006 at 11:26

Hiya,

You need to configure VLAN Trunking between the switches that are used for your VLANs. If you provide more information on your newtork configuration then I can help more.

Sone · 28 Jul 2006 at 11:37

using netgear FSM726S, in stacks of 2 or 3. Buidlings are connecting up using fibre to the switches. (4 stacks)

We have a netgear FSM7328S L3 switch which provides the vlan routing.

edit, currently got 2 vlans but will need more in the future

markwombat · 28 Jul 2006 at 11:44

Its been a while since I worked with VLANs myself but as far as I remember to extend the network one must configure any additional switches with VLAN info and then configure appropiate routing on the L3 switch. It shouldn't be any different from what you say is already in place.

Hope this helps if not shout again.

Sone · 28 Jul 2006 at 11:59

markwombat said:
Its been a while since I worked with VLANs myself but as far as I remember to extend the network one must configure any additional switches with VLAN info and then configure appropiate routing on the L3 switch. It shouldn't be any different from what you say is already in place.

Hope this helps if not shout again.

i'll try and explain where i am confused. For example on the L3 Switchports 1-8 are on VLAN2 (wireless) and the other ports are all just set to default (VLAN1).

The uplink goes from a VLAN1 to port to a VLAN1 port on one of the stacks and all works fine. If i want to extend VLAN2 to this stack what do i do? If i create VLAN2 on there won't i just get another separate VLAN as the uplink is going into VLAN1?

The only way i could see to do it is running 2 uplinks one for each VLAN but there must be a way of doing it with a single uplink

markwombat · 28 Jul 2006 at 13:01

Thanks for the explanation. You should look into VLAN trunking Protocol (VTP) or similar which will trunk numerous VLANs over a single physical connection therefore eliminating one uplink per VLAN.

Hope that helps.

V-Spec · 28 Jul 2006 at 13:54

You need to configure a 802.1q trunk between the 2 switches, this will tag traffic for vlans passing between switches.
You need to make sure that all the switches have the same Vlans in their databases, Cisco uses a mechanism called VTP where switches notify other switches of all the vlans being used, on your switch you may have something similar or have to manually configure.
Just ensure your uplink ports between switches are configued as trunks, and it should be fine.

Sone · 28 Jul 2006 at 13:58

thanks for the help, should crack it with this info.