If we received the "no bootable device" information when operating system start, there are below possible causes:
1, the boot priority has been changed.
2, the boot information was lost.
3, the disk or the raid controller is faulty.
so firstly ,check the boot priority in BIOS, and we found that the first priority boot is network, and not hard drive.
then change the first boot priority to be hard drive and reboot the server, problem fixed.