Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Community Member

Cable from VLAN 1 to VLAN 2: Latency introduce

Hi,

I am little bit confused about this. My friend proposed the scenario like given below using a single switch.

port 1 and 2 in the vlan 1

port 3 and 4 in the vlan 2

port 1: Machine A

Port 3: Machine B

port 2 (VLAN1 )--> Latency-Calculator/generator-Machine --> Port 4 ( VLAN 2).

this is without routing.

so when machine A communicate to the machine B, traffic passes from VLAN1 (port 2) to VLAN 2 (port 4). we have tested this one and it works fine.

I have just a single question, is there is any problem in this scenario when there are lot of traffic, any spanning tree problems or any known vulnerability. I want to know coz we are going to deploy in a very large scale and in the future if it is problem then this will be great loss.

Please give me your suggestions.

Thanks

tauseef

5 REPLIES

Re: Cable from VLAN 1 to VLAN 2: Latency introduce

HI Can you upload the switch configuration where you have connected these all 4 hosts in 2 VLAN's ??

Community Member

Re: Cable from VLAN 1 to VLAN 2: Latency introduce

its a simple configuration like that

int gig 1/0/1

description Machine A

switchport access vlan 1

int gig 1/0/2

description cable connected to port 4

switchport access vlan 1

int gig 1/0/3

description machine B

switchport access vlan 2

int gig 1/0/4

description Cable conencted to port 2

switchport access vlan 2

**********

machine A has IP 10.1.1.1/24

machine B has IP 10.1.1.2/24

both are able to communicate while in different vlans but of same subnet due to cable in the vlans.

Cisco Employee

Re: Cable from VLAN 1 to VLAN 2: Latency introduce

Hi,

In general, it is not recommended to bridge 2 L2 VLAN's together.

Just a question, what kind of network topology you are trying to create? I am interested the one you mentioned "in large scale".

Regards,

jerry

Community Member

Re: Cable from VLAN 1 to VLAN 2: Latency introduce

actually we have a different set of networks for each solution. and for each solution we have a test environment

For solution A we have deployed the 4 ASA 5540 FW's with 8 3750 switches with 2*2 gig LES, 4 lease lines with 4 3600 routers and lot of servers in 2 DC's

we want to create the test environment for that but donot want to spend the same amount of money as on solution A. so that's why we want to use only 1 single switch and to represnet lease lines and LES infrastructure, we want to create the lateny as present in solution A. Servers in a single vlan when communicate to other servers in the same vlan comunicate, they are switched in the hardware. so we are going to deploy the same vlan as the 2 vlans and introduce a latency box in between them to test the applications as they reside in the solution A. too complicated. This type of test scenario we are using for the first time and if is successfull then we will deploy more

Cisco Employee

Re: Cable from VLAN 1 to VLAN 2: Latency introduce

I see. But it is really hard to get some realistic results with 1 switch because the latancy between 2 switch port is minimal.

Regards,

jerry

180
Views
0
Helpful
5
Replies
CreatePlease to create content