[CentOS] Xen hypervisor on CentOS 7.4 with modern UEFI server not booting from grub

Wed Jan 31 20:06:02 UTC 2018
Chris Adams <linux at cmadams.net>

Once upon a time, John Naggets <hostingnuggets at gmail.com> said:
> Jonathan brings it exactly to the point: we have to face UEFI because
> legacy mode is fading out, if I enable legacy mode I can't even boot
> anymore through the network (PXE) as these newer network cards can
> only boot PXE with UEFI.

UEFI PXE is different than BIOS PXE and needs to download different
software from the TFTP server.  I use syslinux for BIOS PXE, but it
doesn't seem to work with UEFI PXE so I use grub2 (I use the secure boot
shim from Fedora to support as many setups as practical).  You can have
both available at the same time (takes a DHCP tweak).

Just like the early days of BIOS PXE however, UEFI PXE clients don't
always seem to do the right thing.  I have an Intel NUC (7th gen), and
it always fails with UEFI PXE.

Chris Adams <linux at cmadams.net>