[lwip-users] Virtual machines in the same host (bridge).

[Norberto R. de Goes Jr.]

Hi All.

I have the following environment:

- host Windows-7 Professional, 64 bits, with two virtual machines (Virtual Box), both  with Fedora-17 Distro, 32 bits; 

- the VM´s network configured as "Internal Network"

I wrote a small "lwip application" based on unix port (community). It runs in VM #1 and a "tap0" device is created with success. In the VM#2 no application is running.

When I "ping" the tap0 IP from the VM#1 the reply is received, no problem. I can see the traces reported by lwip like arp received and arp reply. But when I "ping" the tap0 from VM#2 I have no answer.

Faced with the situation, I followed the steps suggested by another solved threads from this list, for instance:

- http://lists.nongnu.org/archive/html/lwip-users/2004-08/msg00006.html

- http://lists.nongnu.org/archive/html/lwip-users/2012-02/msg00021.html

Basically, the threads show how to configure a linux bridge (br0) and your attached devices.

But I did not get success still. The pings from VM#2 go from the ethernet to the "br0"(VM#1) device and after to the "tap0" device. There the lwIP generates an answer and sends it to the asking host. But then the packages disappear. They do not go back to the "br0" device (seen with dcpdump).

Please, are there any restriction in use the lwip library in virtual machines hosted on the same server? More specifically with linux bridge use?

Thanks!

--

Norberto R. de Goes Jr.
CPqD - DRC
Tel.: +55 19 3705-4241 / Fax: +55 19 3705-6125
address@hidden
www.cpqd.com.br