# Monitor Call Recording Status on an IP Phone

A BLF (Busy Lamp Field) key is a programmable button on a desk phone whose light reflects a status you assign to it. Point it at call recording and it gives the user an immediate, visible signal of whether the current call is being recorded. Assign one per extension through [auto provisioning](/pbx/administrator-guide/auto-provisioning-overview/) so people can confirm at a glance that toggling recording on or off actually took effect.

## Before you begin

The BLF key is pushed to the phone during provisioning, so the device must already be connected to the PBX (Private Branch Exchange, the phone system) and linked to the user's extension. If you haven't set that up yet, start with one of these:

- [Auto Provision IP Phones Remotely via RPS Method](/pbx/administrator-guide/auto-provision-ip-phones-remotely-rps-method/)
- [Auto Provision IP Phones Remotely with Proxy](/pbx/administrator-guide/auto-provision-ip-phones-remotely-with-proxy/)

## Assign the function key

1. Sign in to the PBX web portal and go to **Extension and Trunk > Extension**, then open the extension you want to configure:
   - For a single user, click the edit icon ![Edit](/images/pbx/edit.png) next to the extension.
   - For several users at once, select their checkboxes and click **Edit**.
2. Open the **Function Keys** tab.
3. Fill in a key:
   - **Type**: Choose **BLF**.
   - **Value**: Enter `*1` followed by the extension number you want to watch. For example, extension 1000 becomes `*11000`. The `*1` prefix is the recording-monitor code, and the extension number tells the key whose recording state to subscribe to.
   - **Label**: Optional. Whatever you enter appears on the phone's screen next to the key.
4. Click **Save**.

:::tip
Give each key a **Label** that names the extension it watches (for example `Rec 1000`). On a phone with several BLF keys, the label is the only thing that tells the user which extension each light belongs to.
:::

:::caution
Each phone model offers a fixed number of programmable keys. If you assign more function keys than the device supports, the extra ones are silently dropped and never take effect, so keep the count within the model's limit.
:::

## Reprovision the phone

A phone that is already associated with the extension needs to be reprovisioned before the new key appears:

1. Go to **Auto Provisioning > Phones**.
2. Click the refresh icon ![Reprovision](/images/pbx/refresh.png) next to the phone tied to that extension.

:::caution
Reprovisioning pushes the updated configuration to the phone and refreshes it. Do this while the phone is idle so you don't interrupt a call in progress.
:::

## What the key shows

Once provisioned, the BLF key reflects the recording state in real time:

- **Red**: A live call on the monitored extension is being recorded.
- **Green**: The extension is idle, or its call recording is paused.
- **Off**: The key isn't subscribed to the extension's recording status. Double-check your settings.

:::note
The exact LED colors and behavior can differ from one phone model to another.
:::