Re: [Openvpn-users] OpenVPN 2.0 Final, Branching, and Updates

[Jan van Rensburg <jan.van.rensburg@xxxxxxxxxx>]

Hi,

Some more updates on the Mac problems.

I've made tcpdump logs of the traffic between mail client and the 
server when working via the linux and mac OpenVPN clients. They can be 
downloaded at:
http://xen.epiuse.com/openvpn/tcpdump_log_mac.txt.gz
http://xen.epiuse.com/openvpn/tcpdump_log_linux.txt.gz

> You say that you see this problem when running a multithreaded email
> client over the tunnel.  Can you reproduce with other application 
> traffic
> scenarios, such as by running two simultaneous FTP sessions over the
> tunnel?  If so, can you set up a test where a single FTP session works
> correctly, but attempting a second simultaneous FTP connection fails?

I opened 25 chargen sessions to another server on the same LAN, but it 
kept on connecting fine. I expected it to fail after about the 10th 
session, but no. Some of the sessions did start getting a bit slow, but 
data did come through.

> Have you tried to query the author of the Mac TUN/TAP driver to get his
> intuition on whether this might be a TUN/TAP driver bug, or a bug in
> userspace openvpn, or a configuration issue?

I've email Mattias, who also asked for tcpdump logs, but said "I really 
have no idea what in the driver could cause that multiple connection 
problem you describe. The driver only deals with the IP layer and 
below, so it really doesn't know about connections..."

Jan