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Call Flow Presence Button

FS PBX includes a feature that lets users monitor and toggle a Call Flow using a BLF key.

What the BLF shows​

  • LED ON: Alternate mode is active
  • LED OFF: Normal mode is active
  • Press the button: Toggles the Call Flow

If a PIN is configured on the Call Flow, the user will be prompted to enter it before the toggle is applied.

Configuring the BLF Key​

On Yealink phones (and most SIP phones), add a BLF with:

Type: BLF
Value: flow<EXT> Example: flow333
Label: Day / Night

Replace <EXT> with the Call Flow extension you want to monitor. Example: flow333 for Call Flow extension 333.

This creates a SIP subscription to:

sip:flow333@yourdomain.com

FS PBX then sends real-time presence updates indicating whether the Call Flow is currently in normal mode or alternate mode.

How it works​

The BLF monitors the Call Flow extension directly.

For example:

  • Call Flow extension: 333
  • BLF value: flow333

When the button is pressed, FS PBX toggles the Call Flow status. The BLF lamp then updates automatically to reflect the new state.

Typical use cases​

  • Day / Night mode
  • Open / Closed routing
  • Main office / After-hours routing
  • Holiday routing

Backend FreeSWITCH Configuration Requirements​

You must enable the daemon in:

/etc/freeswitch/autoload_configs/lua.conf.xml

Add or un-comment:

<configuration name="lua.conf" description="LUA Configuration">
  <settings>

    <!-- YOUR EXISTING CONFIG -->

    <!-- FS PBX: Call Flow BLF daemon -->
    <param name="startup-script" value="lua/flow_blf.lua"/>
  </settings>
</configuration>

Important​

You must restart FreeSWITCH to apply changes:

systemctl restart freeswitch

Notes​

  • The BLF URI format is flow<EXT>@domain
  • Example: flow333@yourdomain.com
  • The LED state is tied to the current Call Flow status in FS PBX
  • Some phones may require a reboot or re-registration before BLF updates appear correctly