RE: Client and server on same computer
I'm doing quite a bit of wifi performance testing on a group of clients
sharing a single access point. I run 4 clients at a time from one or
more single PCs with one quad NIC card each (be sure you get one that
really has 4 10/100 ports - a lot of the newer ones use a gigabit NIC
and a 4-port switch). The AP is connected to a dedicated PC running
iperf and ftp servers. I tried to invent a way to integrate the AP into
the client PC, and always concluded that the IP stack would route the
packets internally. QEMU was not included in my attempts, so I'll
investigate it. Also, watch out for circulating packet paths. Many
wifi routers do their packet forwarding with a switch chip, so there's
no real traffic isolation mechanism if both ends of your test setup are
connected to the same wired LAN. (I assume you know this, but accidents
do happen:-)
Thanks,
Bob Jenness
-----Original Message-----
From: owner-iperf-users --at-- dast.nlanr.net
[mailto:owner-iperf-users --at-- dast.nlanr.net] On Behalf Of Daniel Janzon
Sent: Thursday, May 31, 2007 3:56 AM
To: iperf-users --at-- dast.nlanr.net
Subject: Re: Client and server on same computer
Dag Bakke wrote:
> On 05/30/2007 08:09 PM, Daniel Janzon wrote:
>
>> Hello!
>>
>> Does anyone know a neat way to run the iperf server and client on the
>> same computer? The computer has two ethernet cards (eth0 and eth1).
It
>> would be nice to be able to test equipment using a single station.
>>
>>
> What exactly did you intend to test?
>
Wifi equipment. I want to have a test station where you connect
a wifi router on one interface and a wifi usb adapter on another.
Then a button is clicked and test suite is run.
> You can run iperf within QEMU, and bridge the qemu instances to
physical
> ethernet ports. With qemu, you can have a bunch of virtual hosts.
>
>
Say I associate eth0 with one virtual host and eth1 with another.
Will not the traffic between the virtual hosts still bypass the
physical cables between the interfaces and just run through the
kernel of the machine hosting the virtual hosts?
> For proper results, you probably need two separate hosts *doing
nothing
> but running iperf*. You don't want your results to be flawed because
> your host cpu is busy doing something (anything) else. BTDTGTTS.
>
This would be a dedicated machine. If the speed of the ethernet
card(s) is significantly higher than the equipment under test,
I don't see how it could be a problem using a single machine.
/ Daniel