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<blockquote data-quote="acasper" data-source="post: 1694528" data-attributes="member: 367282">I have built a Virtual Machine using Ubuntu 15.10 as a guest under VirtualBox that is configured as a &quot;kiosk&quot; type machine.&nbsp; Add the Oracle extensions pack, and it runs like a champ.The .VHD for this Virtual Machine can be cloned to a USB drive quite easily and will boot on almost any x86 hardware... EXCEPT for Mac.I've tested it against a wide variety of x86-based PCs with roaring success.&nbsp; In fact, there are only a small list of machines that simply refuse to boot from this USB storage.&nbsp; Even newer Win8/10 machines will accept it once you bypass SecureBoot.My testbed in the office for this is a mid-2012 MBP 13-inch with a 2.5ghz i5 and 16gb of RAM running OS-X 10.10.5I did manage to make one USB drive that will boot for Mac by building my kiosk &quot;baremetal&quot;.&nbsp; Put simply, I installed Ubuntu to the USB drive as if it were a SATA device on the Mac.Here's where things get WEIRD.&nbsp; I then (mistakenly) repurposed that same USB drive for something else.&nbsp; On a whim, I tried cloning my &quot;PC-compatible&quot; VHD back to it, and it boots on Mac still!&nbsp; Something outside the scope of normal is going on here.I've even had this mysteriously working USB drive side-by-side against a non-working &quot;clone&quot; of it in a hex debugger and can't find this accidental &quot;secret sauce&quot;.&nbsp; diff returns that the two (as unmounted /dev/sdb and /dev/sdc under a development VM) are in fact different, but no differences are anywhere near the MBR.The &quot;patient-zero&quot; USB drive comes up in the bootloader upon using [Alt/Option] after the startup chime.&nbsp; Any clones show in the menu as well, but upon selecting a drive that isn't this one special case, it presents &quot;No bootable media - press any key&quot;Now, a few catches to this problem...&nbsp; I cannot use rEFIt or rEFInd, nor can I permanently modify the firmware/BIOS/whatever-Apple-calls-it on the target system.&nbsp; These &quot;kiosks&quot; are built for our end users, and I fear for their Mac if we recommend any of that.&nbsp; The goal is to have a plug-n-pray solution that removes the users personal configuration from the equation.&nbsp; A locked-down linux-based kiosk that prevents their (sometimes questionable) configuration choices from interfering with work.What special Apple black-magic am I missing to make a USB drive that isn't from Apple happily boot on a Mac?&nbsp; I'm completely puzzled as to why Apple seems to ignore grub2 unless it was installed baremetal.</blockquote>

[QUOTE="acasper, post: 1694528, member: 367282"] I have built a Virtual Machine using Ubuntu 15.10 as a guest under VirtualBox that is configured as a "kiosk" type machine. Add the Oracle extensions pack, and it runs like a champ. The .VHD for this Virtual Machine can be cloned to a USB drive quite easily and will boot on almost any x86 hardware... EXCEPT for Mac. I've tested it against a wide variety of x86-based PCs with roaring success. In fact, there are only a small list of machines that simply refuse to boot from this USB storage. Even newer Win8/10 machines will accept it once you bypass SecureBoot. My testbed in the office for this is a mid-2012 MBP 13-inch with a 2.5ghz i5 and 16gb of RAM running OS-X 10.10.5 I did manage to make one USB drive that will boot for Mac by building my kiosk "baremetal". Put simply, I installed Ubuntu to the USB drive as if it were a SATA device on the Mac. Here's where things get WEIRD. I then (mistakenly) repurposed that same USB drive for something else. On a whim, I tried cloning my "PC-compatible" VHD back to it, and it boots on Mac still! Something outside the scope of normal is going on here. I've even had this mysteriously working USB drive side-by-side against a non-working "clone" of it in a hex debugger and can't find this accidental "secret sauce". diff returns that the two (as unmounted /dev/sdb and /dev/sdc under a development VM) are in fact different, but no differences are anywhere near the MBR. The "patient-zero" USB drive comes up in the bootloader upon using [Alt/Option] after the startup chime. Any clones show in the menu as well, but upon selecting a drive that isn't this one special case, it presents "No bootable media - press any key" Now, a few catches to this problem... I cannot use rEFIt or rEFInd, nor can I permanently modify the firmware/BIOS/whatever-Apple-calls-it on the target system. These "kiosks" are built for our end users, and I fear for their Mac if we recommend any of that. The goal is to have a plug-n-pray solution that removes the users personal configuration from the equation. A locked-down linux-based kiosk that prevents their (sometimes questionable) configuration choices from interfering with work. What special Apple black-magic am I missing to make a USB drive that isn't from Apple happily boot on a Mac? I'm completely puzzled as to why Apple seems to ignore grub2 unless it was installed baremetal. [/QUOTE]

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