http support

Older versions of PXELINUX supported HTTP by using a hybrid bootloader that also contained gPXE/iPXE, with such images named either gpxelinux.0 or ipxelinux.0.

Since version 5.10, a special PXELINUX binary, lpxelinux.0, natively supports HTTP and FTP transfers, greatly increasing load speed and allowing for standard HTTP scripts to present PXELINUX's configuration file. To use HTTP or FTP, use standard URL syntax as filename; use DHCP options to transmit a suitable URL prefix to the client, or use the "pxelinux-options" tool provided in the "utils" directory to program it directly into the lpxelinux.0 file.

While using HTTP/FTP (syntax), trying to use pxelinux.0 (i.e. without the letter "l" prefix) without iPXE/gPXE running underneath, will result in a "file not found" warning without any explanation as to the cause!