
On 12/02/17 10:47 PM, William Park wrote:
On Sun, Feb 12, 2017 at 03:34:06PM -0500, Scott Sullivan via talk wrote:
Popped the latest multi-arch Debian ISO (8.7.0) into my trusty ZALMAN external drive with virtual CD/DVD function. https://www.newegg.ca/Product/Product.aspx?Item=N82E16811235059
What is "virtual CD"? You mean, you dd ISO to a disk, and the device identifies itself to PC as "CD drive" with the ISO image as "CD"?
Your describing dumping an ISO on any mass-storage device, and hoping that the BIOS is new enough[1] to go 'awh fuckit' and boot the image anyways. The ZALMAN enclosure does something far more clever. It report two separate USB devices. One is a Mass Storage devices, the hard drive in the enclosure. The other is a CD/DVD rom drive. The firmware in the ZALMAN, then knows how to read FAT or NTFS file systems. It will read from a predefined directory on the harddrive, and let you select iso files to 'place in the tray' of the CD/DVD rom drive it's pretending to be. The computer legitimately sees a USB CD/DVD rom, and I can use the controls on the ZALMAN to eject and insert different 'disks' at will. [1]: You go far enough back in PC firmware history, you'll find that BIOS didn't originally and won't do that. It's extra code, but came along as a good idea somewhere to just be agnostic about the storage media, and that propagated forward. There only really a 3-5 companies that write PC bios firmware. https://en.wikipedia.org/wiki/BIOS#Vendors_and_products -- Scott Sullivan