# OS Deployment - Knowledge base

## Configuration of DHCP Option 66/67 for PXE in Sophos Firewall

To configure the filename and next-server details for DHCP in Sophos firewall for IPv4 BOOTP/PXE, follow the steps given below:

1. Open the Sophos Firewall console.
2. Select **Network** → **DHCP** → **Server**.
3. **Next-server:** Enter the IP address of the computer where the central server or distribution server is installed.
4. **Boot file:** Enter **EFI\Boot\bootx64.efi** for UEFI 64-bit machines or **boot\pxeboot.n12** for legacy BIOS machines. Different versions of the Sophos server use different naming conventions. If attempting PXE boot with the above boot file names results in a BSOD, try changing the boot file name to **EFI\\Boot\\bootx64.efi** for UEFI 64-bit machines or **boot\\pxeboot.n12** for legacy BIOS systems.
5. ![Sophos firewall PXE configuration](https://www.manageengine.com/products/desktop-central/images/sophos-config.png)
6. Click **Save**.

**Related Documents:**

- [How to configure DHCP server for PXE?](https://www.manageengine.com/products/desktop-central/os-imaging-deployment/how-to-configure-dhcp-server.html)
- [What is PXE (Preboot Execution Environment)?](https://www.manageengine.com/products/os-deployer/pxe-preboot-execution-environment.html)