×

Warning message

  • Cisco Support Forums is in Read Only mode while the site is being migrated.
  • Cisco Support Forums is in Read Only mode while the site is being migrated.

2 Vlans Talking to each other

Unanswered Question

I am rookie when it comes to vlans so please keep this in mind.


What I am trying to accomplish is we have a 10.16.0.0/16 network.

I want to create 2 vlans (to seperate traffic)

like have 10.16.1.1-20 on 1 vlan and 10.16.1.21-40 on another, can I do this and have them talk to each other and accomplish seperate broadcast domains with the vlan?


Thanks again

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
r-godden Wed, 02/06/2002 - 01:42
User Badges:

if you use vlans then you will need to route between

them.


for 20 hosts per vlan use 27 bit mask 255.255.255.224 this will divide your addresses into

0-31 32-63 etc

ejgonzalesiii Wed, 02/06/2002 - 08:45
User Badges:

Yes this will work only if the router that you are using supports trunking.


-Henry

paquino Fri, 02/08/2002 - 14:25
User Badges:


Ok


1. It seems like the 10.16.1.1-20 and the 10.16.1.21-40 fall within the same 255.255.0.0 IP subnet. In this case saparating these ip addresses with a vlan would totally isolate isolate the machines from one another.


vlan 1 10 .16 .1. 1-20

vlan 2 10 .16 .1. 21-40

255.255.0. 0


these are the same ip subnet.


2. If you meant the subnet 10.16.0.1-20 and

10.17.0.1-20 then they would be seperate broadcast domains but unable to talk to one another without a layer 3 interface for routing. So the answer is no you still wouldnt have full connectivity.


Lemme know if this helps


Sincerely,

Paul Aquino

CSE

Cisco Systems

ryan.vaughn Mon, 02/11/2002 - 07:57
User Badges:

I have done something similar to this, but not exactly what you are looking at.

I use Bay Networks Baystack 350T switches to seperate my vlans behind the router. Normally, I only vlan seperate subnets, but it should also work for vlans inside a subnet. We use this to run a single line into a building and seperate the tenant traffic via vlans to a single interface on a cisco router. I have never gotten a cisco catalyst switch to do the same thing I have seen with Baystack switches. I am not sure if this is because of functionality or inexperience on my part with catalyst switches (probably the latter of the two.)

I would NOT recommend taking this path however. If you want to seperate the 2 networks, I would recommend routing the two segments of the network between two interfaces on a router in two seperate networks. I just believe in presenting all options ;c)

Actions

This Discussion