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+ Cylinder/Head/Size Hell Is Not Over
+ $Id$
+
+
+
+Nowadays, you can boot Linux without every relying on CHS
+(Cylinder/Head/Size):
+
+- CHS information on partition table is obsolete and not used anymore.
+It was causing the 1024th cylinder limitation:
+ - disallowing partitions above 8GiG. Problem overcome using 32bits linear
+ addressing in partition table.
+ - disallowing to boot on partition above 8GiG (due to int13 limitation used
+ in bootloaders). Problem overcome using int13 extensions (EDD)
+
+Logical CHS (Cylinder/Head/Size) and physical CHS are not related anymore.
+Especially the size of a hard drive is not a multiple of the number of
+Cylinders.
+
+
+The problem is that many tools still rely somewhat heavily on CHS information.
+- most tools adjust partitions on cylinder boundary
+- some tools compute the size of the disk based on CHS (eg: fdisk)
+
+
+Resulting problems in various tools:
+
+- last partition not cylinder boundary adjusted, and overrun CHS computed size
+ - fdisk
+ > Total allocated sectors %d greater than the maximum %d
+ - cfdisk (need confirmation)
+ > FATAL ERROR: Bad primary partition %d: Partition ends after end-of-disk
+ or
+ > FATAL ERROR: Bad logical partition %d: Partition ends after end-of-disk
+ - Partition Magic (version?)
+ (doesn't like it, what error message?)
+ - Windows <= 98se, Windows Me
+ (doesn't like it, what error message?)
+
+ Tools handling it correctly:
+ - parted and so diskdruid in RedHat >= 7.2 (or is it 7.x?)
+ - diskdrake >= Mandrake 8.2
+ - Windows XP (need confirmation)
+
+ Tools using the full size of the disk, and so causing pbs with fdisk/cfdisk/...:
+ - diskdrake >= Mandrake 8.2
+ - parted (what about diskdruid??)
+
+- disagreement between CHS and linear address
+ - parted
+ > "Warning: Unable to align partition properly. This probably means that
+ > another partitioning tool generated an
+ > incorrect partition table, because it didn't have the correct BIOS
+ > geometry. It is safe to ignore,but
+ > ignoring may cause (fixable) problems with some boot loaders.
+ > Ignore Cancel ? C
+ - lilo
+ > Warning: Kernel & BIOS return differing head/sector geometries for device 0x80
+ > Kernel: 38792 cylinders, 16 heads, 63 sectors
+ > BIOS: 1023 cylinders, 255 heads, 63 sectors
+ > Device 0x2100: Inconsistent partition table, 2nd entry
+ > CHS address in PT: 48:0:1 --> LBA (771120)
+ > LBA address in PT: 48384 --> CHS (3:3:1)
+ > The partition table is *NOT* being adjusted.
+
+