EFI PXE boot using grubx64.efi - Large images

[Locane]

Hello all!  I hope this is the appropriate list for Grub2 questions, if not
please let me know.

As a self-taught DevOps person, I'm missing some knowledge.

At the moment, I'm trying to boot a 1.2 gigabyte CentOS 7.4 livecd from an
EFI PXE menu using grubx64.efi, and I'm running in to the error "Cannot
allocate initrd".

I've read from this stack overflow question
<https://superuser.com/questions/1128891/pxeboot-grub2-uefi-with-very-large-initrd>
that this is probably due to grub being unable to work with an initial
ramdisk of that size, so I've taken to trying to load a smaller one first,
and then load and swap to the larger one.

Does anyone have experience with getting around this size limitation?

Does anyone have experience setting up an initrd that loads a larger initrd
in to memory, and then swaps to it as the root file system?

Thank you in advance.