On Mon, Aug 09, 2010 at 09:00:35PM -0400, Eric Thibodeau wrote: > As per ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/v2.18/v2.18-ReleaseNotes : > > fdisk(8): > - supports new command line option "-c" to switch off DOS mode > - uses 1MiB offset for the first partition > (all these changes are already in the release 2.17.2) > > I presume the 1MiB offset is to accomodate for grub2. No, the offset (and alignment to MiBs) is there for compatibility and portability (raids, 4K sector disks, win7, ...). > My attempts in partitioning a drive with a 1MiB post-MBR gap failed sfdisk has tendency to use CHS to calculate partition size, it means that 1MiB does not have to be on cylinder boundary. You have to use sectors as basic units. The another problem is that it checks against cylinder boundary, so you need to use --force ... > with the following command line call: > > sfdisk -uM -L /dev/sda <<-EOF try to use -uS, it seems that sfdisk rounds to cylinders if magabyte is specified (this should be fixed). > 1,256,fd > ,512,fd > ,,fd > ; > EOF for example: sfdisk --force -uS /dev/sdb <<EOF 2048 102400 0x83 104448 1206272 0x83 EOF result: sfdisk -uS -l /dev/sdb Device Boot Start End #sectors Id System /dev/sdb1 2048 104447 102400 83 Linux /dev/sdb2 104448 1310719 1206272 83 Linux My suggestion is to use fdisk rather than sfdisk, if you really need create partitions from script than is probably the best way to to create the partitions by fdisk and then dump the layout by sfdisk -uS -d <dev> > part.txt and then call from scripts sfdisk <dev> < part.txt or use the latest versions of GNU Parted. Karel -- Karel Zak <kzak@xxxxxxxxxx> http://karelzak.blogspot.com -- To unsubscribe from this list: send the line "unsubscribe util-linux-ng" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
