Active calls

From VoIPmonitor.org
Revision as of 19:46, 6 January 2026 by Admin (talk | contribs) (Add documentation about dealing with duplicate entries in Active Calls view - filtering by carrier IP and other causes)


This page describes the Active Calls view, which provides real-time monitoring of ongoing calls in the VoIPmonitor GUI.

Overview

The Active Calls view displays current calls in real time and allows you to listen to G.711 calls live (requires sniffer version 7 or newer). The view refreshes automatically according to the configured refresh interval (default: 2 seconds).

Communication with Sniffer

Live call data is fetched from the VoIPmonitor sniffer instance through the manager TCP port 5029. If calls are not displayed, verify that the web server can reach this port:

ℹ️ Note: If calls are not displayed, verify that the web server can reach the sniffer's manager port 5029.

Test connectivity: 

telnet localhost 5029

Direct URL Access

You can open the Active Calls view directly using this URL format: 

http://your-server/admin.php?activecalls=1

Filtering Calls

The filter box adapts to the type of input provided. Calls can be filtered by:

  • National or international (via combo box)
  • Sensor
  • IP address or IP prefix
  • Phone number or prefix
  • Call-ID

Filter Syntax Examples

Input Description
192.168.% Filters calls with source or destination IP starting with 192.168.x.x
00 Filters calls where the number starts with 00
abc123 Searches for exact Call-ID match
%abc123% Searches for Call-ID containing "abc123" (substring match)

💡 Tip: By default, Call-ID search matches the full Call-ID string. To search for a substring, add the % wildcard character to the start and/or end of the search string.

Dealing with Duplicate Entries

The Active Calls view may show duplicate entries for what appears to be a single call. This often happens when calls pass through multiple SIP gateways or carriers, creating separate legs that are all captured by the sniffer.

Filtering by Carrier IP

To consolidate the view and display one entry per call, use the filter field with the carrier's IP address:

  • Enter the specific carrier's IP address (e.g., 203.0.113.50)
  • The view will display only the SIP leg between your system and that specific carrier
  • Other legs are filtered out, making each listed item correspond to a single call

ℹ️ Note: This approach works best when each call traverses different carriers. Redirected calls using the same carrier IP for both inbound and outbound legs may still appear twice.

Other Causes of Duplicates

If filtering by IP does not resolve the duplication, the duplicates may be caused by:

  • Multiple sensors: Different sensors capturing the same mirrored traffic. Filter by a specific Sensor ID using the dropdown.
  • SIP forking: A single INVITE sent to multiple destinations (e.g., simultaneous ringing to desk phone and mobile). These are separate call legs and display correctly as two entries.

For more information on how sensors handle duplicate Call-IDs, see the Sniffer_distributed_architecture documentation.

Bottom Graphs

The bottom section of the Active Calls view displays graphs showing the top callers grouped by:

  • Caller IP address
  • Called IP address

Customizing Column Visibility

The Active Calls view allows you to show or hide columns based on your preferences. This is useful when:

  • You want to reduce visual clutter and focus on specific information
  • Certain columns contain data that is causing performance issues (e.g., parsing errors in the Proxy column)
  • Your display has limited screen space

To hide or show columns:

  1. Locate the column header area at the top of the table
  2. Click on the column visibility icon (typically a column or grid icon) or look for a "Show columns" dropdown menu
  3. Uncheck columns you want to hide, check columns you want to show
  4. The view will update immediately with your selection

Your column visibility preferences are stored in the GUI configuration (saved in the MySQL custom_config table) and persist across sessions.

Troubleshooting Performance Issues

If the Active Calls view becomes unresponsive or slow, particularly when displaying certain columns like "Proxy":

Temporary workaround: Hide the problematic column using the column visibility method above.

If the GUI is completely unresponsive:

  • Connect directly to the GUI database
  • Check the custom_config table for column visibility settings
  • Clear or modify the relevant configuration entries
  • Contact support with SSH access to the GUI host for investigation

Information to provide for support:

  • A SIP PCAP dump of a problematic call (to identify data causing parsing errors)
  • A mysqldump of the voipmonitor.custom_config table (to review current column configuration)

Programmatic Access to Active Calls

In addition to viewing active calls in the GUI, you can programmatically retrieve active call data for automation and integration purposes.

GUI API (Recommended for Centralized Systems)

The VoIPmonitor GUI provides a web API endpoint listActiveCalls that retrieves active calls from all connected sensors/probes. This is the preferred method for centralized monitoring environments.

Example: 

curl -X POST 'http://yourserver/php/api.php?task=listActiveCalls&user=USER&password=PASSWORD&params={"sensorId":"1"}'

Sniffer Manager API (For Individual Sensors)

For direct access to a single sensor instance, use the sniffer service's manager API on port 5029. The listcalls command retrieves active call data from the specific sensor.

  • Method: TCP connection to port 5029
  • Documentation: Manager API

Example: 

echo 'listcalls' | nc localhost 5029

The manager API supports filtering by caller number, called number, IP addresses, and other criteria. See the Manager API documentation for advanced filtering examples.

Choosing the Right Method

Use the GUI listActiveCalls API when:

  • You have multiple sensors/probes and need centralized access
  • You want to query all connected sensors from a single endpoint
  • You are building external integrations that need filtered results

Use the sniffer manager API when:

  • You need direct access to a specific sensor instance
  • You are running scripts locally on the sensor host
  • You require low-latency queries without GUI involvement

AI Summary for RAG

Summary: Active Calls provides real-time monitoring of ongoing VoIP calls with live listening capability for G.711 codec. Calls are fetched via manager port 5029 and can be filtered by IP, number, sensor, or Call-ID. The view may show duplicate entries due to multiple call legs passing through different carriers - filtering by carrier IP can consolidate these displays. Other causes of duplicates include multiple sensors capturing the same traffic and SIP forking (simultaneous ringing). Column visibility can be customized and settings persist in the database. Programmatic access is available through two methods: the GUI's listActiveCalls API for centralized monitoring of multiple sensors, and the sniffer's manager API (listcalls command) for direct sensor access.

Keywords: active calls, real-time monitoring, live calls, manager port 5029, call filter, column visibility, custom_config, G.711 listening, listActiveCalls API, programmatic access, automation, manager API, listcalls command, duplicate entries, multiple call legs, carrier IP filter

Key Questions:

  • How do I view active/live calls in VoIPmonitor?
  • Why are active calls not showing in the GUI?
  • How do I filter calls by IP address or phone number?
  • How do I hide or show columns in the Active Calls view?
  • What port is used for fetching live call data?
  • How can I programmatically check if a call to a specific phone number is currently active?
  • What is the difference between listActiveCalls API and the sniffer's manager API?
  • How do I retrieve active calls from all connected sensors?
  • How do I query active calls from a single sensor directly?
Retrieved from "https://www.voipmonitor.org/doc/index.php?title=Active_calls&oldid=9391"