Page tree

Starting from firmware version all deskphones equipped with a USB port can store PCAP traces on a mass-storage device connected via USB. In this case the trace size is limited only by the free space of the USB device.

In order to enable this feature you need to:

  • Enable the usb_storage_pcap phone setting
  • Unzip and save the flag file named pcap.flg on the USB device root directory
  • Plug the USB device into the phone


Step-by-step guide:

  1. Enable the usb_storage_pcap you can do it via provisioning or via phone web interface clicking on Advanced -> QoS/Security   

  2. Unzip and save the "flag file" pcap.flg into the USB stick root directory

  3. Unplug the USB device from the computer (please follow the required steps to safely unplug the device)

  4. Plug the USB device into the phone USB port, the phone should detect the storage device

  5. At this point the phone starts saving the pcap trace onto the USB device. Once you have reproduced the issue you can unmount and unplug the USB device. Unmounting the device before unplugging is fundamental in order to avoid data corruptions, the USB device can be un-mounted pressing the Menu key, selecting Maintenance and then Unmount USB disk:

  6. Now your are ready to plug the USB device into your computer and start analysing the saved PCAP trace:

Be aware that in heavy network load scenarios some packets can be missing from the saved PCAP trace. In this case the best way to obtain a trace is using a network hub or a switch with port mirroring.