RHEL clone and UEFI booting, aka the dreaded unable to mount initrd error

[NiKiZe]

iPXE does nothing, however, if a http server responds with a gzip stream that stream is decompressed, some http servers does send such headers for .gz which means you will have a uncompressed image in memory.

Yes everything is done one thing at a time.

And kernels pre 3.16 is buggy in regards to handling initrd in efi mode - it is corruption of the image itself - you could always try to decompress initrd server side and load it uncompressed in case that triggers the bug.

I would look for the original patch that was added in 3.16 to fix this issue to see what exactly is going on, but I don't think there is no way to avoid it - you are just lucky if it doesn't happen.