---
title: "Configure a custom iPXE script to boot your server from the OVHcloud API"
description: "Find out how to configure a custom iPXE script to boot your server from the OVHcloud API"
url: https://docs.ovhcloud.com/en/guides/bare-metal-cloud/dedicated-servers/ipxe-scripts
lang: en
lastUpdated: 2024-02-27
---
# Configure a custom iPXE script to boot your server from the OVHcloud API

## Objective

:::warning
This article is intended for experienced users who have at least basic knowledge about [Preboot Execution Environment (PXE)](https://en.wikipedia.org/wiki/Preboot_Execution_Environment) and its implementation being used at OVHcloud: [iPXE](https://ipxe.org/).

:::

In the OVHcloud Control Panel
, it is possible to specify a boot mode among a predefined list: primary disk or rescue.

With the [OVHcloud API](https://eu.api.ovh.com/)
, you can define custom scripts.
Using a custom script can be useful in the following use cases:

- You are using a volatile OS that you don't want to install on disk and that remains only in memory.
- You have a multi-cloud strategy and one of the other cloud providers you use doesn't offer the OS you want to install, nor does it offer an alternative solution such as [BringYourOwnImage](/en/guides/bare-metal-cloud/dedicated-servers/bring-your-own-image.md).
- You want a standard installation process whatever the cloud provider is, so you have built your own rescue installation image to fully manage the complete OS installation of your dedicated server.

## Requirements

- A [dedicated server](https://www.ovhcloud.com/en-gb/bare-metal/) **ready to be booted/rebooted** in your OVHcloud account.
- Access to the [OVHcloud API](https://eu.api.ovh.com/).

:::warning
Restarting a dedicated server can cause outage of all services that only depend on this dedicated server.

:::

## Instructions

### Generate an iPXE script for your dedicated server [](#)
#### Change server iPXE script [](#)

🇪🇺EU▾

[PUT/dedicated/server/{serviceName}](https://eu.api.ovh.com/console/?section=/dedicated/server&branch=v1#put-/dedicated/server/-serviceName-)

Specify your script within the `bootScript` attribute directly.

#### Get the server iPXE script [](#)

🇪🇺EU▾

[GET/dedicated/server/{serviceName}](https://eu.api.ovh.com/console/?section=/dedicated/server&branch=v1#get-/dedicated/server/-serviceName-)

You can see your script within the `bootScript` attribute.

For example:

```json
{
    "noIntervention": false,
    "name": "nsXXXXXXX.ip-XXX-XXX-XXX.eu",
    "rack": "SXXXBXX",
    "commercialRange": "fs",
    "os": "debian11_64",
    "rootDevice": null,
    "rescueMail": null,
    "linkSpeed": 1000,
    "bootScript": "#!ipxe\necho Boot first local hdd in LEGACY mode\nsanboot --no-describe --drive 0x80\nexit 1\n",
    "reverse": "nsXXXXXXX.ip-XXX-XXX-XXX.eu",
    "state": "ok",
    "ip": "XXX.XXX.XXX.XXX",
    "bootId": null,
    "newUpgradeSystem": false,
    "datacenter": "sbg3",
    "professionalUse": false,
    "supportLevel": "pro",
    "serverId": 123456,
    "powerState": "poweron",
    "monitoring": false
}
```

You can now reboot your server and it will use your [iPXE](https://ipxe.org/) to boot.

### Changing boot modes [](#)
You can now switch back to disk or rescue boot from the OVHcloud Control Panel
 (see our guide on [Activating and using rescue mode](/en/guides/bare-metal-cloud/dedicated-servers/rescue-mode.md)
), or the [OVHcloud API](https://eu.api.ovh.com/)
.
#### Switch to disk [](#)

🇪🇺EU▾

[PUT/dedicated/server/{serviceName}](https://eu.api.ovh.com/console/?section=/dedicated/server&branch=v1#put-/dedicated/server/-serviceName-)

Specify `1` in the `bootId` attribute.


🇪🇺EU▾

[GET/dedicated/server/{serviceName}](https://eu.api.ovh.com/console/?section=/dedicated/server&branch=v1#get-/dedicated/server/-serviceName-)

You can now see that the attribute value `bootScript` is null.

## Go further [](#)
[Restarting your dedicated server](/en/guides/bare-metal-cloud/dedicated-servers/getting-started-with-dedicated-server.md#reboot)

[Activating and using rescue mode](/en/guides/bare-metal-cloud/dedicated-servers/rescue-mode.md)

[iPXE - open source boot firmware](https://ipxe.org/)

Join our [community of users](https://community.ovhcloud.com/).