Introduction
This document describes how to trace Pan Tilt Zoom (PTZ) signals through the logs of the Cisco Video Surveillance Manager (VSM) system.
Background Information
You need to look at:
- The connection from the client to the media server.
- The connection from the media server to the camera.
Trace PTZ Activity
In order to see if the media server gets the PTZ request from the client PC, use this command:
tail -f ims.log | vsmdbg | grep -i "CameraName"
Once you have the device ID (e7e66b2, for example), use this command:
vsmdbg httpserver_access.log | grep 'PTZ' | grep e7e66b2 | grep 'doPTZ'
If the messages get to the Media server's driver, the next step is to see what is going on on the wire. You can get the outbound traffic to the Camera with the use of Linux command tcpdump:
tcpdump -s0 host <camera-addr> -w CameraName_ptz.pcap
Wireshark has a good option that allows it to decode the messages for you. Look for Analyze > Decode as... > [+] > RTP.
The exact steps to do that vary with the version of Wireshark.
To simplify the output one can remove the Real-time Transport Protocol (RTP) and RTPc packets and add this to the filters:
!(rtp) && !(rtcp)