On gio, 2011-11-10 at 15:01 +0100, Jim Meyering wrote: > Christian wrote: > > On mer, 2011-11-09 at 00:16 +0100, Christian wrote: > >> Hi, > >> > >> I created a GPT table on a file (1 MB), using parted 2.2. > >> Looking at the hexdump seems that the CHS-start-sector of the GPT > >> partition may not be correct. Those are MBR (64 byte) partitions: > >> > >> Status CHS Type CHS LBA start LBA sectors > >> 00 000100 EE FEFFFF 01000000 FF070000 > >> 00 000000 00 000000 00000000 00000000 > >> 00 000000 00 000000 00000000 00000000 > >> 00 000000 00 000000 00000000 00000000 > >> > >> CHS start bytes are HEAD: 00, SECTOR: 01 CYLINDER: 00. > >> > >> Using the formula: > >> > >> LBA = (CYL * NHEADS + HEAD) * NSECTORS + SECTOR - 1 > >> > >> LBA = (0 * 4 + 0) * 32 + 1 - 1 > >> > >> LBA = 0 > >> > >> But the GPT header is at LBA 1 (as the LBA start field 01000000). > >> > >> This is an error or CHS values are ignored? > >> > >> Many thanks! > >> > >> Christian. > > > > Parted 3.0 have this "error" too. > > Thanks, but it's not an error. > That first sector is called the protective MBR. > Note the "type" of EE. > > https://secure.wikimedia.org/wikipedia/en/wiki/GPT_Disk
Oh, thanks for your response! :) Sorry but I'm a little confused. If the value of CHS (0, 0, 1 (wich corresponds to LBA 0)) is correct, why the LBA field indicates LBA 1? The CHS values must be ignored by a partitioning program? Thanks! Christian.
