---
title: "Changing the PTP Domain Number in VX Enterprise and VX Prime+"
slug: "changing-the-ptp-domain-number-in-vx-enterprise-and-vx-prime"
updated: 2024-12-31T09:23:54Z
published: 2024-12-31T09:23:54Z
canonical: "docs.telosalliance.com/changing-the-ptp-domain-number-in-vx-enterprise-and-vx-prime"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.telosalliance.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Changing the PTP Domain Number in VX Enterprise and VX Prime+

## Scope

This procedure applies only to VX Enterprise and VX Prime+ units and does not include Legacy VX and VX Prime (fanless engine).

> [!NOTE]
> This procedure may involve 3rd party software. Even though the software we mention is free and available, Telos Alliance can neither take responsibility for nor provide support for it in any way.

## Description

The default value for PTP domain for AES67 is 0, where the VX Enterprise and Prime Plus systems operate. Sometimes, there is a need to use a different domain; for example, 127 is the default value for SMPTE 2110. This parameter is not currently exposed to the user interface, and the change needs to be made to PTP4L from the command line. This technote will guide you through the process.

### Install 1.3.1 Release or higher

1. Version 1.3.1 or higher is required.

[Update instructions and release notes for VX Enterprise and Prime+ version 1.3.1](/v1/docs/update-instructions-and-release-notes-for-vx-enterprise-and-prime-version-131)
2. Log in to the SSH terminal using these credentials:

```plaintext
User name: root
Password:  <contact telos for your password>
```

The System ID is required to be able to provide root credentials. System ID is found by clicking the Status link in your VX Web UI under the System heading.

![](https://cdn.document360.io/57e3cd80-d493-453c-9672-ad1b043dadc3/Images/Documentation/3be67808-40a0-4172-8f23-eafa2a34909f-image.png)

1. Use vi to edit the `ptp4l.cfg` file

Using this command:

```plaintext
vi /etc/local/ptp4l.cfg
```

This opens the ptp4l config file in the vi text editor.

### 4. Add the following to the end of the file:

```plaintext
domainNumber 127
```

### 5. Save Changes and reboot the VX.

## Let us know how we can help

If you have further questions on this topic or have ideas about improving this document, please [contact us](https://www.telosalliance.com/support-request).