Ok, your initrd.img doesn't support nfs : chroot /pxeroot vi /etc/initramfs-tools/initramfs.conf change the line : BOOT=local to...
It's crazy, I never build my own kernel. I will continue to investigate.
Can you try to make the virtual device in chroot /pxeroot mknod /dev/nfs b 0 255
Can you send me the content of your /etc/exports? for the error "ALERT! /dev/nfs does not exist. Dropping to a shell!", there is a problem with...
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