On 06/09/14 10:52, Alexey Rybalko wrote:

Hello to all!

I encountered strange issue with rtpengine: voice during a call is heard like random binary data. (Video freezes during a video call). _It goes fine during 2-3 seconds_ before the media flow becomes glitched. It's related to SRTP calls only (RTP-SRTP, SRTP-RTP, SRTP-SRTP). RTP calls through mediaproxy are ok.

Used platform: Red Hat Linux 6.4, rtpengine (3.3.0 ?, latest form GitHub), kamailio (4.2.0-dev6) + websocket module. I have successfully installed (manually) mediaproxy daemon, Kamailio module, iptables library and kernel module. Kernel module was loaded (lsmod lists it, there are file in /proc/mediaproxy/0) and iptables were configured as expected.

Hard to tell what the problem is without looking at the RTP traffic. The log looks fine. The delay you mentioned could indicate that it might be the kernel module that's misbehaving. Perhaps you can try the same thing again, but without the iptables rules installed (and/or without the kernel module loaded), and see if that makes a difference.

Mediaproxy log looks fine except of a few suspicious messages "No support for kernel packet forwarding available". I'm not sure they are related to the mentioned problem but I would like to have working kernel support. Attached example is for SIP-to-websocket call.

Those are actually expected on the RTCP ports, as RTCP is not supported by the kernel module. I suppose the log messages shouldn't actually be there for those ports.

That would be great if you make any suggestions/comments on this issue. Need to mention that I haven't saw such problems on Debian Linux.

That's curious, perhaps something went wrong when compiling the kernel module then? I have to admit that I have zero experience with rtpengine on Red Hat myself.

Couple of other questions:

• What does message "Call-ID to delete not found" means?

Your SIP proxy sends two "delete" messages to rtpengine for some reason. The first one already tears down the whole call, so the second one triggers an error. No harm done, but also unnecessary.

• "x_tables" is mentioned as required in the documentation for rtpengine

kernel module (xt_MEDIAPROXY). Seems to be for Debian only. Is it required for other distros?

The x_tables module is a prerequisite for all xt_* modules. If you don't have x_tables as a module (doesn't show up in lsmod), then perhaps it's compiled into the kernel. You wouldn't be able to use iptables at all without x_tables present.

cheers