How to boot a non-Secure Boot UEFI system using PXE.

1. Create a directory containing a boot/grub/grub.cfg file with the following contents.

   set timeout=5
   menuentry 'Linux diskless' --class os {
      insmod net
      insmod efinet
      insmod tftp
      insmod gzio
      insmod part_gpt
      insmod efi_gop
      insmod efi_uga
      insmod ofnet
      # dhcp, tftp server in my network
      set net_default_server=192.168.125.1
      # auto dhcp setup did not work for me, no idea why
      # net_bootp
      # ok let's assign a static address for now
      net_add_addr eno0 efinet0 192.168.125.99
      echo 'Network status: '
      net_ls_cards
      net_ls_addr
      net_ls_routes
      echo 'Loading Linux ...'
      linux (tftp)/5.1/vmlinuz console=tty0 console=ttyS0 boot=live nopersistent nonetworking noeject
   fetch=http://192.168.125.1/17.0.1/vyatta.iso
      echo 'Loading initial ramdisk ...'
      initrd (tftp)/17.0.1/initrd.img
   }

2. Mount the Vyatta NOS ISO.

   mkdir isomnt 
   mount vyatta.iso isomnt

3. Create the bootx64.efi bootloader.

   grub2-mkstandalone -d
   /var/lib/tftpboot/17.0.1/isomnt/boot/grub/x86_64-efi/ -O x86_64-efi
   --fonts="unicode" -o bootx64.efi boot/grub/grub.cfg

4. Point your DHCP server to the newly created bootx64.efi bootloader.