opensand team mailing list archive

[Andrei POPOV <nyandoma@xxxxxxxxx>]

Julien,
I also wanted to ask about routing: is there any difference on which 
interface to point a route towards the networks behind GW or ST? I mean, 
before the start of OpenSand we have only physical interfaces on ST and 
GW but when we start OpenSand - it brings up virtual "opensand" 
interfaces. So what should be configured as a next hop on workstations: 
IP addresses of physical interfaces of ST/GW or IP addresses of virtual 
new born interfaces?

Andrei

On 25/07/2013 17:08, Julien BERNARD wrote:
> Hi Andrei,
> > While  carrying  out a series of experiments I faced a problem when at
> > some point Satellite Terminal stops working.
> > The  testbed  topology  is  presented in the attached file. I generate
> > multiple  traffic  flows (1 to 9) from  the  Sender  to  the 
> > Receiver  in the
> > direction  from GW to ST using iperf with MSS = 1400 bytes. The buffer
> > of the GW (max_fifo) reduced to the value of 2500.
> > At  some  point  of the experiments (after 40-100 seconds form flow(s)
> > start)  the  ST  stops  processing  traffic (sometimes ST indicator in
> > OpenSand  Manager  turns red, sometimes it's still green but TCP flows
> > don't flow).
>
> I tried to reproduce your problem in your conditions but among many 
> tests I only encounter a crash a couple of times and this is not 
> enough to investigate.
>
> My tests:
>  - I configure GW fifo size to 2500 and  start OpenSAND
>  - I launch 9 or more iperf flows with the command "iperf -c 
> 192.168.19.1 -p 3004 -M 1400 -t 500 -m" in a workstation behind the GW
> Am I missing something ? Do you have a problem for each test or is it 
> random ?
>
> > In  the  core.log  I  see  the  following errors after which ST stops
> > working:
> >
> > Jul 24 15:28:40 router st: [encap] [Mpeg.cpp:deencapsulate():193] 
> > ERR: [Mpeg::Context::deencapsulate] cannot create a burst of packets, 
> > drop packet
> > Jul 24 15:28:42 router st: [encap] [Mpeg.cpp:deencapMpeg():515] ERR: 
> > [Mpeg::Context::deencapMpeg] MPEG frame(s) lost (MPEG CC = 12, CTXT 
> > CC = 8), reset context, sync on PUSI
> > Jul 24 15:28:42 router st: [encap] [Mpeg.cpp:deencapMpeg():515] ERR: 
> > [Mpeg::Context::deencapMpeg] MPEG frame(s) lost (MPEG CC = 15, CTXT 
> > CC = 2), reset context, sync on PUSI
> > Jul 24 15:28:43 router st: [dvb_rcs_tal] 
> > [bloc_dvb_rcs_tal.cpp:connectToQoSServer():1138] 
> > [Tal][BlocDVBRcsTal::connectToQoSServer] service on TCP/12000 is not 
> > available
> > Jul 24 15:28:44 router st: [encap] [Mpeg.cpp:deencapMpeg():536] ERR: 
> > [Mpeg::Context::deencapMpeg] PUSI not set in current MPEG frame, drop it
> > .............................
> > Jul 24 15:28:56 router st: [encap] 
> > [../../src/common/IpPacketHandler.h:build():89] ERR: 
> > [IpPacketHandler::build] cannot get IP version
> > Jul 24 15:28:56 router st: [encap] [Ule.cpp:deencapUle():397] ERR: 
> > [Ule::Context::deencapUle] cannot create a IP packet, drop the ULE 
> > packet
> > Jul 24 15:28:56 router st: [encap] [Ule.cpp:deencapsulate():191] ERR: 
> > [Ule::Context::deencapsulate] cannot create a burst of packets, drop 
> > packet
> > Jul 24 15:28:56 router st: [encap] 
> > [../../src/common/IpPacketHandler.h:build():89]
> The errors seems to be in the encapsulation plugins, could you try 
> with GSE on forward link instead of MPEG/ULE ?
> You may have to install libopensand-gse-encap-plugin on hosts and 
> libopensand-gse-encap-plugin-manager on manager.
>
>
> > Could you please tell me what can cause this problem?
>
> I think there is a bug in OpenSAND appearing at high throughput but I 
> need a way to reproduce it easily in order to fix it.
>
> Best regards,