updated server root folders

docs/pxe-boot.md

@@ -7,12 +7,14 @@ The `pxe-boot` host serves HTTP boot assets for iPXE clients.
 - Hostname: `pxe-boot`
 - Web service: nginx on TCP port 80
 - PXE root: `/srv/pxe`
-- iPXE entry script: `/srv/pxe/boot.ipxe`
-- Generated iPXE menu: `/srv/pxe/menu.ipxe`
-- TFTP fallback script: `/srv/pxe/boot/autoexec.ipxe`
+- HTTP root for scripts and images: `/srv/pxe/http`
+- TFTP root for first-stage bootloaders: `/srv/pxe/tftp`
+- iPXE entry script: `/srv/pxe/http/boot.ipxe`
+- Generated iPXE menu: `/srv/pxe/http/menu.ipxe`
+- TFTP fallback script: `/srv/pxe/tftp/autoexec.ipxe`
 - Boot binaries copied from the Nix `ipxe` package:
-  - `/srv/pxe/boot/ipxe.efi`
-  - `/srv/pxe/boot/undionly.kpxe`
+  - `/srv/pxe/tftp/ipxe.efi`
+  - `/srv/pxe/tftp/undionly.kpxe`
 
 ## Directory Layout
 
@@ -20,12 +22,18 @@ The host creates these directories with systemd tmpfiles:
 
 ```text
 /srv/pxe
-/srv/pxe/boot
-/srv/pxe/nixos
-/srv/pxe/ubuntu
-/srv/pxe/rescue
+/srv/pxe/http
+/srv/pxe/http/images
+/srv/pxe/http/nixos
+/srv/pxe/http/ubuntu
+/srv/pxe/http/rescue
+/srv/pxe/tftp
 ```
 
+Mount shared image storage under `/srv/pxe/http`, preferably
+`/srv/pxe/http/images` unless a menu entry expects files in a specific
+directory such as `/srv/pxe/http/nixos`.
+
 The HTTP iPXE chain is:
 
 ```text
@@ -35,9 +43,6 @@ undionly.kpxe or ipxe.efi
   -> http://192.168.2.247/menu.ipxe
 ```
 
-The same scripts are also exposed under `/boot/` for compatibility with older
-checks and any DHCP option that already points there.
-
 The generated menu currently exposes entries for:
 
 - NixOS installer
@@ -46,8 +51,9 @@ The generated menu currently exposes entries for:
 - Reboot
 
 Kernel and initrd artifacts for installer or rescue entries must be placed under
-the matching `/srv/pxe/<entry>/` directories by an operator or a separate build
-process. This repository defines the service and menu, not the installer images.
+the matching `/srv/pxe/http/<entry>/` directories by an operator or a separate
+build process. This repository defines the service and menu, not the installer
+images.
 
 ## Validation
 
@@ -62,10 +68,6 @@ After deployment by an operator, basic service checks are:
 ```bash
 curl http://pxe-boot/boot.ipxe
 curl http://pxe-boot/menu.ipxe
-curl http://pxe-boot/boot/menu.ipxe
-curl http://pxe-boot/boot/autoexec.ipxe
-curl -I http://pxe-boot/boot/ipxe.efi
-curl -I http://pxe-boot/boot/undionly.kpxe
 ```
 
 During a successful BIOS chainload, TFTP should deliver `undionly.kpxe` once,