Active Calls

Real-time monitoring of ongoing VoIP calls with live listening capability (G.711 codec, sniffer v7+).

Overview

Feature	Details
Auto-refresh	Default: 2 seconds
Communication	TCP port 5029 (Manager API)
Live listening	G.711 codec only (requires sniffer version 7+)
Direct URL	`admin.php?activecalls=1`

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

Filtering

The filter box adapts to the input type. Available filters:

Sensor - dropdown selection
IP address/prefix - e.g., 192.168.%
Phone number/prefix - e.g., 00 (international)
Call-ID - exact or substring match

Filter Input	Matches
`192.168.%`	Source/destination IP starting with 192.168.x.x
`00`	Numbers starting with 00
`abc123`	Exact Call-ID match
`%abc123%`	Call-ID containing "abc123"

💡 Tip: Use % wildcard for substring matching in Call-ID searches.

Duplicate Entries

Duplicates often appear when calls traverse multiple SIP gateways/carriers.

Solutions:

Filter by carrier IP - Enter the specific carrier IP to show only one leg per call
Filter by sensor - If multiple sensors capture the same mirrored traffic
SIP forking - Simultaneous ringing to multiple destinations are separate legs (expected behavior)

For distributed sensor architectures, see Sniffer_distributed_architecture.

Show Call Info

Displays detailed SIP packet information for active calls when clicking on a call entry.

⚠️ Warning: Requires VoIPmonitor version 2024.09.1+ and can significantly increase CPU load.

Enable via config file:

# /etc/voipmonitor.conf
active_call_info = yes

systemctl restart voipmonitor

Enable via GUI: Settings > Sensors > wrench icon > enable active_call_info

Column Visibility

Customize visible columns via the column header menu ("Show columns"). Settings persist in the custom_config database table.

💡 Tip: Hiding problematic columns (e.g., "Proxy") can resolve performance issues caused by parsing errors.

Bottom Graphs

The bottom section displays top callers/called grouped by IP address.

Programmatic Access (API)

GUI API (Centralized)

Query active calls from all connected sensors via listActiveCalls:

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

See WEB_API#listActiveCalls for details.

Sniffer Manager API (Direct)

Query a single sensor directly via port 5029:

echo 'listcalls' | nc localhost 5029

Method	Use Case
GUI `listActiveCalls`	Multiple sensors, centralized monitoring, external integrations
Manager API `listcalls`	Single sensor, local scripts, low-latency queries

Troubleshooting

Problem	Solution
No calls displayed	Verify port 5029 connectivity: `telnet localhost 5029`
Duplicate entries	Filter by carrier IP or sensor ID
Slow/unresponsive view	Hide problematic columns (e.g., "Proxy")
GUI completely frozen	Connect to DB, clear entries in `custom_config` table

For support tickets, provide:

SIP PCAP dump of problematic calls
mysqldump of voipmonitor.custom_config table

AI Summary for RAG

Summary: Active Calls provides real-time monitoring of ongoing VoIP calls via TCP port 5029. Features include: live listening (G.711 only, sniffer v7+), filtering by IP/number/Call-ID/sensor, and column customization. Duplicate entries occur when calls traverse multiple carriers - filter by carrier IP to consolidate. "Show Call Info" feature (v2024.09.1+) displays SIP packet details but increases CPU load. Programmatic access available via GUI API (listActiveCalls for multi-sensor) or Manager API (listcalls for single sensor). Settings stored in custom_config table.

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

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?
Why do I see duplicate entries for the same call?
How do I enable "Show Call Info" feature?
What port is used for active call data?
How do I programmatically query active calls?
What is the difference between listActiveCalls and listcalls?
How do I customize column visibility?
What version is required for SIP packet view in active calls?

Active calls