Re: testing cabling and NIC hardware with one machine

[Christopher Paul]

On 10/25/17 10:20 PM, Tony Sarendal wrote:

Configure the interfaces into separate rdomains.

/T
Yup that works. For sure I know the packets are traveling along the wire 
using rdomains now. But I wonder how much of the RTT on each packet is 
due to the kernel/driver/rdomain code now. And also due to this test 
platform being a virtual machine in Linux/XEN environment.


The ping response I get is, across the wire, more than what I got 
without the rdomains: round-trip min/avg/max/std-dev = 
0.415/0.530/0.890/0.165 ms, not bad but not what I'd like to see from 
10GbE. A large std-dev, relatively, and not quite as low as I'd expect 
for 10GbE. As this test instance currently is a Xen guest, the interface 
is an xnf driver; the 10GbE is bridged on a Linux Xen server's device. 
But based on this working, I may be able to justify some hardware 
allocations happening so I can build a platform natively OpenBSD.


Thanks, Tony, for the good tip.

CP

Re: testing cabling and NIC hardware with one machine

[Tony Sarendal]

Configure the interfaces into separate rdomains.

/T

2017-10-25 21:17 GMT+02:00 Christopher Paul :

> Hi Misc,
>
> I have been tasked with setting up a benchmark platform to test NICs and
> network cables. I'd like to do this on one PC. So I want to send packets of
> different protocols out of one interface and into the other, across/thru
> the NICs and whatever type/lengths of cabling I am using. The problem I am
> having is that if I configure two interfaces on the same server, either on
> the same network or not, the kernel is smart enough to know to not need to
> use the actual wire (ethernet cable) in order to transmit the packet from
> one interface to the other. Which I guess I was aware of, and of course it
> makes a lot of good sense for a normal situation, but in this case, is a
> block on my project.
>
> So I'm wondering is this sort of kernel-fooling I want to do possible with
> OpenBSD? Or for that matter, any OS?
>
> May be I need to set them up as a bridge? If I did that I could set it up
> with forwarding, yeah? Something like that I guess I will try next.
>
> Many thanks for those of you who read this and offer any ideas && Long
> Live OpenBSD,
>
> CP
>
>