[Unattended] find-boot-device line 212 Error

Hello,
While trying to install via pxe unattended with asus-p8b75-m-csm resulted in error "Unable to determine boot device at /usr/bin/find-boot-device line 212". Linux lspci reports the following ATA device:
00:1f.5 IDE interface: Intel Corporation Panther Point 2 port SATA Controller [IDE mode] (rev 04)
Can someone provide a fix? Many thanks!
Kwon


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