PXE Server Configuration
=======================

This guide provides a **step-by-step procedure** to configure a **PXE + ISO + Kickstart server**
using the **OpenCHAI Manager Tool**.  
It enables automated provisioning of HPC, AI, and login nodes over the network.

The PXE server setup is fully automated using **Ansible**, with a **Python-based CLI**
to manage DHCP client definitions in an enterprise-safe manner.


Overview
--------

The PXE server configuration performs the following tasks:

- Installs and configures **DHCP, TFTP, HTTP, and PXE boot services**
- Mounts and exports OS ISO content over HTTP
- Generates PXE boot menus dynamically
- Configures **static DHCP reservations** (MAC → IP mapping)
- Supports **interactive review and modification** of DHCP clients
- Allows execution to be restricted to specific nodes using Ansible ``-l``


PXE-Server Setup to boot service nodes
---------------------
::

  # Go to the OpenCHAI directory where the repository was cloned from GitHub
  cd OpenCHAI

**Define DHCP Clients**

Create or edit the DHCP client input file:

::

  vim ./servicenodes/dhcp_clients_mac.txt

Format:

::

  <node_name>,<mac_address>,<ip_address>

Example:

::

  master01,00:0C:29:43:18:B4,172.10.3.101
  master02,00:0C:29:43:18:B5,172.10.3.102
  login01,00:0C:29:43:18:B6,172.10.3.103

This file is used to generate static DHCP reservations.


Step 2: Run PXE Server Setup
----------------------------

Run the PXE server setup script:

::

  bash servicenodes/pxe_server_setup.sh

During execution:

- All DHCP clients are displayed in a table
- You are prompted to update MAC or IP values if required
- Final confirmation is requested before execution


Step 3: Restrict Execution (Optional)
-------------------------------------

To limit execution to a specific PXE server node or inventory group:

::

  bash pxe_server_setup.sh headnode

or

::

  bash pxe_server_setup.sh pxe_servers

This internally maps to the Ansible ``-l`` (limit) option.



Step 4: PXE Boot Client Nodes
-----------------------------

Once the PXE server setup completes successfully:

1. Power on target nodes
2. Enable **PXE / Network Boot** in BIOS or UEFI
3. Select network boot option
4. Installation proceeds automatically using Kickstart

Bonus: PXE Client Node 
-----------------------

On the PXE client nodes, wait for a minute the following screen is appearing.

.. image:: ../../_static/pxe_client_boot_time.png
   :alt: PXE Client Node Message Screen
   :align: center
   :width: 90%