Configuring Verba for passive recording

Owned by Kiss, Mate
Jul 31, 2018
3 min read

Step 1 - Prerequisites

Step 1 - Configure your network mirror ports

Plan where you want to tap your network. For a good recording both signaling and RTP traffic related to the recorded phones/trunks must be seen on the monitoring port.
You can read more about this here:

Step 2 - Active the Passive Recorder Service

Step 1 - Login to the web interface with System administrator rights.

Step 2 - Navigate to the System / Servers menu item and select the corresponding server from the list.

Step 3 - Click on the Service Activation tab.

Step 4 - Activate the following services using the 'Activate this service' button:

Verba Passive Recorder Service

 (Activate this service)

Step 3 - Configure the Passive Recorder

Go to the Change Configuration Settings tab in the Verba Server management screen (see in steps above).

Step 1 - Set gateway addresses to determine call direction info (outgoing/incoming/internal) (Common Configuration/Recording Settings)

Step 2 - Select interface connected to monitoring port (Passive Recorder Configuration/Basic Settings/Recording interface)

Step 3 - Select video call recording mode (Passive Recorder Configuration/Advanced Settings/Record video call as audio)

Step 4 - If you are interested in incomplete calls (calls canceled, called busy…), enable logging of them (Passive Recorder Configuration/Advanced Settings/Record incomplete calls)

Step 5 - If you are interested in DTMF recording configure it

Step 6 - After making your changes clicking on the Save button in top right corner of the configuration tree

Step 7 - Follow the instruction in the yellow stripe above the configuration tree to apply changes to Verba services.

Step 8 - Start the Verba Passive Recorder Service in the Service Control tab

If the services start properly, you can start making test calls from your configured endpoints and verify them by searching for phone calls.

Configuration parameter reference

Basic settings

  • Recording interface: NIC on which the recorder is listening to network traffic
  • Audio format:  storage format for audio only calls
  • Bidirectional/Stereo recording: if storage format allows then caller is recorded on left called on right channel in stereo media file
  • Automatic Gain Control: enables AGC on voice streams
  • Conference Resources IP addresses: IP addresses of conference resources, used for recognizing conference calls
  • Experimental H.323 support: enables recording of H.323 calls. Module is still under development
  • SIP support enabled: enables recording of SIP calls
  • Call timeout: stucked in calls after RTP timeout are cleared after this interval

Advanced settings

  • Capture buffer size: packet capture buffer size in megabytes
  • Database cache folder: database cache file folder
  • RTP address translation enabled: recording calls at SBC/RTP proxy usually needs to translate local/private addresses reported by phones behind NAT to the addresses seen in the IP header rewritten by NAT (public address). You can enable a special mechanism that tries to fix RTP address issues here.
  • PCM mixer buffer length: length of mixing buffer in miliseconds. Greater value provides better quality but higher memory load and bursty CPU usage.
  • RTP stream reorder buffer length: length of RTP reorder buffer can be controled here. Greater value provides better reordering but increases memory usage
  • Record video call as audio call: if enabled only audio part of video calls are recorded, else video calls are recorded in Verba Media Format
  • Media format fallback: in case of not supported codecs, too many streams, not supported streams, transcoding quality issue, the recorder can intelligently change storage format to different kind of codecs which might preserve the recording in more optimal quality.
  • Filter duplicated recordings by caller-called: only one call with the same participants will be recorded. This can avoid call duplication in case of SBC/RTP proxy recording related to inbound and outbound legs.
  • Skip calls without media: Do not insert CDR at calls where no RTP has been received/processed
  • SIP URI modification: control how to transform SIP uri
  • Record incomplete calls: if enabled CDR related to not established calls due to call cancellation, busy/not available response will be recorded with appropriate end cause info