How to redirect PXE boot to another TFTP or to HTTP?

Question

I would like to make the installation of Linux always possible in my LAN. So, I have configured PXE boot on my DHCP server. The DHCP server points to the TFTP server, and it normally loads menus and can boot kernels. All files were taken from syslinux.org distribution.

Also I know that Ubuntu ISO normally contains some PXE files for network boot. But I don't want to replace all my PXE menus with ones from the distro.

Is it possible to redirect or chain (don't know how to say) from my PXE menu to another PXE menu and / or serve it differently (via HTTP)?

The following straightforward config does not work (nothing happens, no errors):

DEFAULT vesamenu.c32
PROMPT 0

MENU TITLE MyTitle

LABEL install1404server
MENU LABEL Install Ubuntu 14.04.1 Server AMD64
KERNEL http://192.168.10.25/boot/ubuntu-14.04.1-server-amd64/install/netboot/ubuntu-installer/amd64/linux.0
APPEND vga=788 initrd=http://129.168.10.25/boot/ubuntu-14.04.1-server-amd64/install/netboot/ubuntu-installer/amd64/initrd.gz

All these files are accessible via HTTP.

Directory is follows:

$ ls
ldlinux.c32   libutil.c32  moon640.jpg  pxelinux.0    sagittarius-a.jpg
libcom32.c32  menu.c32     moon800.jpg  pxelinux.cfg  vesamenu.c32
$ pwd
/var/lib/tftpboot

UDPATE

I found that:

1) To work with HTTP, lpxelinux.0 should be used instead of pxelinux.0.

2) To redirect to another menu, its menu binary should be set as KERNEL, and config file should be set as APPEND (not sure).

3) TFTPD does not support symlinks for now.

Answer 1

in your ../tftp/pxelinux.cfg/default:

LABEL Chain to Cobbler
       MENU LABEL Install New OS
       comboot pxechain.com
       append cobbler.my.net::/pxelinux.0

you'll need a recent version of syslinux, of course, but EL6+ should have what you need.