For older systems, run the bootstrap in BIOS mode. For BIOS CD/DVD, choose **ISO**. For BIOS USB, choose **USB**
Download the bootstrap image. Next, we will burn the bootstrap image.
## Burn the Zero-OS Bootstrap Image
We show how to burn the Zero-OS bootstrap image. A quick and modern way is to burn the bootstrap image on a USB key.
### CD/DVD BIOS
For the BIOS **ISO** image, download the file and burn it on a DVD.
### USB Key BIOS+UEFI
There are many ways to burn the bootstrap image on a USB key. The easiest way that works for all operating systems is to use BalenaEtcher. We also provide other methods.
For **MAC**, **Linux** and **Windows**, you can use [BalenaEtcher](https://www.balena.io/etcher/) to load/flash the image on a USB stick. This program also formats the USB in the process. This will work for the option **EFI IMG** for UEFI boot, and with the option **USB** for BIOS boot. Simply follow the steps presented to you and make sure you select the bootstrap image file you downloaded previously.
> Note: There are alternatives to BalenaEtcher (e.g. [usbimager](https://gitlab.com/bztsrc/usbimager/)).
**General Steps with BalenaEtcher:**
1. Download BalenaEtcher
2. Open BalenaEtcher
3. Select **Flash from file**
4. Find and select the bootstrap image (with your correct farm ID)
5. Select **Target** (your USB key)
6. Select **Flash**
That's it. Now you have a bootstrap image on Zero-OS as a bootable removable media device.
#### CLI (Linux)
For the BIOS **USB** and the UEFI **EFI IMG** images, you can do the following on Linux:
Here the * is to indicate that you must adjust according to your disk. To see your disks, write lsblk in the command window. Make sure you select the proper disk!
*If you USB key is not new, make sure that you format it before burning the Zero-OS image.
#### Rufus (Windows)
For Windows, if you are using the "dd" able image, instead of writing command line, you can use the free USB flashing program called [Rufus](https://sourceforge.net/projects/rufus.mirror/) and it will automatically do this without needing to use the command line. Rufus also formats the boot media in the process.
## Additional Information (Optional)
We cover some additional information. Note that the following information is not needed for a basic farm setup.
### Expert Mode
You can use the [expert mode](https://v3.bootstrap.grid.tf/expert) to generate specific Zero-OS bootstrap images.
Along the basic options of the normal bootstrap mode, the expert mode allows farmers to add extra kernel arguments and decide which kernel to use from a vast list of Zero-OS kernels.
#### Use a Specific Kernel
You can use the expert mode to choose a specific kernel. Simply set the information you normally use and then select the proper kernel you need in the **Kernel** drop-down list.
#### Disable GPU
You can use the expert mode to disable GPU on your 3Node.
In the expert mode of the Zero-OS Bootstrap generator, fill in the following information:
- Farmer ID
- Your current farm ID
- Network
- The network of your farm
- Extra kernel arguments
- ```
disable-gpu
```
- Kernel
- Leave the default kernel
- Format
- Choose a bootstrap image format
- Click on **Generate**
- Click on **Download**
### Bootstrap Image URL
In both normal and expert mode, you can use the generated URL to quickly download a Zero-OS bootstrap image based on your farm specific setup.
Using URLs can be a very quick and efficient way to create new bootstrap images once your familiar with the Zero-OS bootstrap URL template and some potential varations.
Note that the arguments and the kernel are optional.
The following content will provide some examples.
#### Zeros-OS Bootstrapping
On the [main page](https://v3.bootstrap.grid.tf/), once you've written your farm ID and selected a network, you can copy the generated URL of any given image format.
For example, the following URL is a download link to an **EFI IMG** of the Zero-OS bootstrap image of farm 1 on the main TFGrid v3 network:
```
https://v3.bootstrap.grid.tf/uefimg/prod/1
```
#### Zeros-OS Expert Bootstrap
You can use the generated sublink at the **Generate step** of the expert mode to get a quick URL to download your bootstrap image.
- After setting the parameters and arguments, click on **Generate**
- Add the **Target** content to the following URL `https://v3.bootstrap.grid.tf`
- For example, the following URL sets an **ipxe** script of the Zero-OS bootstrap of farm 1 on the main TFGrid v3 network, with the **disable-gpu** function enabled as an extra kernel argument and a specific kernel:
