---
title: Scan a KNX line to monitor its participants in Boss’nX
description: Detect the participants of a KNX line through a Kloud’nX gateway and add them in one go to Boss’nX reachability monitoring, without creating duplicates.
canonical: https://wiki.can-nx.com/en/guides/boss-health-scan/
language: en
product: Boss’nX
audience:
  - administrateur
  - installateur
context: "Boss’nX on a computer: Scan the KNX bus wizard of the Network health page"
---

# Scan a KNX line to monitor its participants in Boss’nX

Context: Boss’nX on a computer: Scan the KNX bus wizard of the Network health page

The **Scan the KNX bus** wizard in Boss’nX probes a KNX line through a Kloud’nX gateway, lists the participants that answer and creates their monitors in **Network health** in one go. Use it to monitor the reachability of several participants without entering them one by one.

The scan does not delete, add or repair any physical device. It replaces neither an ETS import, nor creating datapoints in a component, nor [selecting the addresses to log](https://wiki.can-nx.com/en/guides/boss-knx-monitoring/).

## Before you start

- Your role has **View network health** and **Manage network health**.
- You are working on a computer, in the relevant supervision.
- The Kloud’nX gateway and the line to scan are confirmed for the installation.

## Start scanning a line

1. Open **Menu → Network health**, then click **Scan the KNX bus**.
2. In **KloudnX gateway**, choose the gateway whose bus must be probed. The first one in the list is offered by default: check that it is the right one.
3. In **Line to scan**, enter **area.line**, each number from 0 to 15. **1.1**, the example offered initially, designates a line; **1.1.5** designates a participant and is not suitable for this field.
4. Read the warning: the scan probes **256 addresses**, takes about **40 seconds** and generates traffic on the bus. Avoid starting it during an ETS commissioning.
5. Click **Start the scan**. Check the reminder of the gateway and the line, then follow the counters of probed addresses and detected participants.
6. Wait for **Scan complete — … participants detected over … addresses probed in … s.** before preparing the addition.

The announced duration is approximate.

## Choose the participants to add

1. Review each physical address. New participants are checked initially: uncheck those you do not want to monitor.
2. An **already monitored** row shows the name of the existing monitor and its checkbox is disabled. It matches a monitor with the same gateway and the same physical address, even a suspended one. To reactivate it, use [Edit → Monitoring enabled](https://wiki.can-nx.com/en/guides/boss-health-manage/).
3. On the new rows, adapt the suggested name, **Participant …**, in the field on the right of the address. Choose names that make the devices recognizable, without confusing name and address.
4. Check the **… participants selected** counter, then click **Add … participants to monitoring**.
5. Wait for the window to close.

## Close or cancel the wizard

- Before starting, **Cancel** closes the window without starting the scan.
- During the scan, **Cancel the scan** closes the wizard, but the gateway continues the probing already started. Wait for it to finish before starting another one on the same gateway.
- On the results, **Close** discards the choices not added. Once the addition has started, closing the window does not undo the participants already created.

## Check the result

1. Find the new rows in **Monitored devices**, with **All** or **KNX**.
2. Each added participant is an active KNX monitor, with the detected physical address, an initial interval of **60 seconds** and no location. The scan does not fill in a group address.
3. If necessary, open the pencil **Edit** of each row to review its gateway and address, choose a location or adjust the interval.
4. Then follow the state of each monitor using [the meaning of the states](https://wiki.can-nx.com/en/guides/boss-health/). A discovered address shows that the participant answered during the scan; its availability over time is read in network health.

## Troubleshooting

If an expected participant is missing, first check the line and the gateway before considering it absent or faulty.

| Message | What to do |
| --- | --- |
| **Select a KloudnX gateway.** | Choose the confirmed gateway. If none is suitable, have the project’s gateways checked. |
| **Invalid line — area.line format (e.g. 1.1).** | Correct the two numbers separated by a dot. Use neither a group address nor a complete participant address. |
| **A scan is already running on this gateway. Try again in a minute.** | Wait for the existing scan to finish, then close and reopen the wizard if a new attempt is still needed. |
| **KNX bus unreachable — the gateway could not open a bus connection.** | Have the chosen gateway and its bus access checked. The message concerns this access, not a particular participant. |
| **Gateway needs an update — this version cannot scan the KNX bus yet.** | Contact support to have the suitable update confirmed, without inferring a procedure from this message alone. |
| **The scan did not answer in time. Check the gateway and try again.** | Check the gateway and your session, then try again once after closing and reopening the wizard. If these checks have already failed, contact support. |
| **The scan failed. Try again.** | Note the message and the context, without assuming a specific cause. If a new attempt in the right context fails, contact support. |

### Resume after a failed addition

With **Adding the participants failed. Try again.**, some participants may have been created before the failure. **Do not immediately restart adding the same selection.**

1. Close the wizard and locate the rows already added in **Network health**.
2. Once the previous scan has finished, reopen **Scan the KNX bus** with the same gateway and the same line.
3. After the new scan, check the **already monitored** rows and select only the participants that are still missing.
4. Start adding them only once, then check the list. If the state remains uncertain or the addition fails again, contact support before creating anything else.

## Contact support

Write to support@can-nx.com with the building, the gateway, the line, the message, the participants already visible and the attempts made. A screenshot without sensitive data can help.

French labels: **Menu → Santé réseau → Scanner le bus KNX**, **Passerelle KloudnX**, **Ligne à scanner**, **Lancer le scan**, **Annuler le scan**, **Scan terminé**, **déjà surveillé**, **Ajouter … participants à la surveillance**, **Fermer**, **L'ajout des participants a échoué. Réessayez.**