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Re: netinst.iso on USB flash drive -- unexpected results


Richard Owlett wrote:
> Should have I expected this result?

As far as the parted report is concerned: Yes.

> parted /dev/sdb print
>  Warning: The driver descriptor says the physical block size is 2048
>  bytes, but Linux says it is 512 bytes.
>   Partition Table: mac

It probably complains that the Apple Partition Map blocksize 2048 is
not the same as the device block size. That's ok. Device block size 512
is expected for the use of the partition tables inside the bootable
debian-cd ISOs.

(It is rather questionable whether the Apple Partition Map is used
 by any boot firmware. Especially since there is no HFS+ partition.)

There is also an MBR (aka "DOS") partition table. Inquire by

  $ /sbin/fdisk -l debian-9.0.0-i386-netinst.iso
  Device                         Boot Start    End Sectors  Size Id Type
  debian-9.0.0-i386-netinst.iso1 *        0 767999  768000  375M  0 Empty
  debian-9.0.0-i386-netinst.iso2       3868   4475     608  304K ef EFI (FAT-12/16

The type "Empty" of partition 1 is an essential feature, not a bug.
With any other type, EFI would not accept partition 2.

With the 9.0.0 ISO i get from parted

  Number  Start   End     Size   File system  Name   Flags
   1      2048B   6143B   4096B               Apple
   2      1980kB  2292kB  311kB               EFI

The first partition is the Apple Partition Map itself.
The second partition marks the same block range as the EFI partition in the
MBR partition table. But parted's kB are merchant's KB (1000, not 1024),
whereas fdisk reports blocks of 512 bytes.
  3868 * 512 = 1,980,416

Have a nice day :)