Re: [help] Regarding Socket programming in GENI with OpenVswitch

[Niky Riga]

Hi Amjad,

I am adding geni-users for wider distribution.

Although I don't know what type of controller you are running, or what
type of OVS, but my guess is that you are running a user space OVS
(maybe from one of the online tutorials) and you are only using Xen VMS.

This is a known problem, where for some reason although the traffic
makes it to the interface of the VM it is not delivered to the
application. To verify that can you run a tcpdump -i eth1 on the server
and verify that the packets are getting to the interface from the client?

One solution is to use a different image that has kernel OVS installed.
Unfortunately we haven't had a chance to fully test it.

Please start a new slice and setup your topology this time using this
URL as the image for the OVS:
https://www.utahddc.geniracks.net/image_metadata.php?uuid=37d27f35-77ea-11e3-a957-000000000000

Let us know if that fixed your problem.

Good luck,
Niky

Md. Amjad Hossain wrote:
> Hi,
>
> I have a linear topology ( client --- OVS --- Server) with middle one setup
> with OpenVswitch. I can ping from client machine to server machine ( and
> vis-va) when controller is running ( here controller resides in the same
> machine where OVS running) .
>
> I need to connect a c++ client to the server through socket. I can connect
> it using server IP of eth0 ( console port) but can't connect when I use IP
> of eth1 for the server. The switch works with IP of eth1 ( as all machine's
> eth0 are in same network, so, they don't need the switch and controller
> functional).
>
>
> Please help me. how can I solve the problem to make connect between client
> and server sockets through OVS.
>
> Please have a look to my topology for more details. When I am trying to
> connect 10.10.10.2:30001 from client, the OVS shows it is forwarding
> something, but finally the client windows shows "can't bind the port".
>
> Regards
> Amjad
>

[Niky Riga]

Hi Amjad,

It will take a while for the node to come up because it has to copy over
the image and then boot the host. Did you node ever come up?

From looking at the errors i am not sure if the kernel module was
compiled.

What is the output of:

ovs-ofctl show br0 ?

--niky


Md. Amjad Hossain wrote:
> Hello Niky,
>
> Thanks for your relpy.
>
> Please have a look to the file " OVS install and configuration.txt" in the
> attachment to see procedure I have followed to setup OVS, controller and
> hosts.
>
> Also please have a look to the output I have observed from tcpdump -i eth1
> on the server in the file "output.txt". This output is for running client
> for two times ( client tried to connect to server twice). The output file
> also contains the output observed in POX controller.
>
>
> I have already tried the image you have sent. I have tried with three
> machine linear connection where I have run OVS image in the middle machine.
> Problem is the machine where image is running never become ready. Please
> see the attached snapshot.
>
>
> In this situation could you please any other solutions?
>
> Best Regards
> Amjad