Conference bridges enable multi-party calls — essential functionality for team meetings and group calls on a self-hosted PBX. This guide covers configuring conference bridges in Asterisk.
Understanding Asterisk's ConfBridge Application
See How to Install Asterisk PBX on a VPS for base setup — ConfBridge is Asterisk's modern conferencing application, replacing the older MeetMe application, offering better audio quality and more configuration flexibility.
Step 1 — Define a Conference Bridge Profile
[default_bridge]
type=bridge
max_members=20
record_conference=no
internal_sample_rate=autoBridge profiles define the technical behavior of the conference (participant limits, recording, audio quality settings) — separate from the user-facing experience settings covered in the user profile.
Step 2 — Define a User Profile
[default_user]
type=user
announce_join_leave=yes
music_on_hold_when_empty=yes
admin=noUser profiles control the experience for regular participants — announcements, hold music behavior when waiting for others to join.
Step 3 — Define an Admin User Profile
[admin_user]
type=user
admin=yes
announce_join_leave=yesAdmin users typically have additional privileges — muting other participants, ending the conference, and other moderation capabilities appropriate for meeting hosts.
Step 4 — Set Up a Dialplan Extension for the Conference
[internal]
exten => 8000,1,ConfBridge(1234,default_bridge,default_user)Dialing extension 8000 connects to conference room 1234, using the defined bridge and user profiles — the dialplan entry point users actually dial to join.
Setting Up PIN Protection
[default_bridge]
type=bridge
pin=123456A PIN adds basic access control, preventing unauthorized parties from joining if they somehow discover the conference extension number.
Setting Up Recording for Conference Calls
[default_bridge]
record_conference=yes
record_file=/var/spool/asterisk/monitor/conf-${STRFTIME(${EPOCH},,%Y%m%d-%H%M%S)}.wavSee How to Set Up Call Recording and Compliance Logging for the broader recording/compliance considerations, applied specifically to conference recording here.
Configuring Conference Waiting Music
See music-on-hold configuration in your Asterisk setup — ensures a professional experience for participants who arrive before others, rather than dead silence.
Handling Announce Join/Leave Notifications
Toggle whether participants hear an announcement (name recording or tone) when others join/leave — genuinely useful for smaller meetings (awareness of who's present), potentially disruptive for larger conferences with frequent joins/leaves.
Testing Conference Quality with Multiple Participants
Test with genuinely multiple simultaneous participants (not just two) before relying on conference bridges for important meetings — audio mixing quality and server resource usage scale with participant count in ways not always apparent from smaller tests.
Common Errors
Audio quality degrades noticeably with more participants — verify your server has adequate CPU resources for the audio mixing load (see VPS Requirements for VoIP and Communication Servers), since conference audio mixing is genuinely more compute-intensive than simple two-party calls.
Continue Reading
- How to Install Asterisk PBX on a VPS
- How to Set Up Call Recording and Compliance Logging
- VPS Requirements for VoIP and Communication Servers
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