In current behavior to netboot over tftp we have to set option 150 in the dhcp server, but this option is not available in the PXE specification. We cannot properly recognize user intentions based only on the RFC 1048 data from PXE and always boot over nfs.
Replacing option 150 by option 66 which is stored on the vm_rfc1048 data makes possible to skip bootp() request for boot over tftp too.
Sponsored by: Oktawave