# fdisk and Advanced format drives[solved]

## jserink

Hi All;

I have just taken delivery of my new Dell Precision M4600 and am preparing to wipe it and do it up as I want. it comes with a 512e HDD:

livecd ~ # hdparm -i /dev/sda

/dev/sda:

 Model=ST9500423AS, FwRev=0001DEM1, SerialNo=5WR0C0HL

 Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs RotSpdTol>.5% }

 RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=4

 BuffType=unknown, BuffSize=16384kB, MaxMultSect=16, MultSect=16

 CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=976773168

 IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}

 PIO modes:  pio0 pio1 pio2 pio3 pio4 

 DMA modes:  mdma0 mdma1 mdma2 

 UDMA modes: udma0 udma1 udma2 udma3 udma4 udma5 *udma6 

 AdvancedPM=yes: unknown setting WriteCache=enabled

 Drive conforms to: unknown:  ATA/ATAPI-4,5,6,7

 * signifies the current active mode

Dell gives out a pamphlet that tells one to go to www.dell.com/512e-drives which tells you what your dealing with. from googling the linux sources it means that basically the 'actual' sector size on the HDD is 4096 but it shows/emulates 512 for backward compatibility to other systems. Ok, so I came up with my planned partition table below:

Partition	Type  Size (G)   File system   Sector Size  Start Sector    Approx size in sectors (512)   End Sector   Mod (8)

1p             Boot       0.04   ext2                       512               64                                78,125         78,192         0

2p             Windows    40   NTFS                      512         78,256                          78,125,000    78,203,256        0

3p             Extended   					

3               Swap        20   Swap                      512   78,203,320                          39,062,500    117,265,824       0

4               var           25   ext4                       512  117,265,832                          48,828,125    166,093,952       0

5               usr           25   ext4                       512  166,093,960                          48,828,125    214,922,088       0

6               opt          15    ext4                       512  214,922,096                          29,296,875    244,218,968       0

7               tmp         10    ext4                       512  244,218,976                          19,531,250    263,750,224        0

8               root         10    ext4                       512  263,750,232                          19,531,250    283,281,488        0

9               shr           43    ext3                      512  283,281,496                           83,984,375   367,265,872         0

10             home      300    ext4                       512  367,265,880                          585,937,500   953,203,376        0

Not shown are the other columns in my spread sheet where I do the partition arithmetic in sector sizes of 4096 and make sure that the 512 start and end values correspond to the 4096 sector sizes.

Now, my problem is that I fired up fdisk:

livecd ~ # fdisk -v

fdisk (util-linux-ng 2.18)

And the lowest sector value it will allow is 2048.

WHY? According to all I have read, 64 is just fine so why is fdisk only allowing me to start at 2048?

Does anyone have any ideas on this?

Cheers,

johnLast edited by jserink on Tue Sep 20, 2011 3:29 am; edited 1 time in total

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## jserink

Ok, I followed what fdisk told me what do do and found out that the 8 512 byte sectors I was leaving between each partition in the extended section was not enough, fdisk wanted more. I just followed fdisk and ended up with this:

livecd ~ # fdisk -l /dev/sda

Disk /dev/sda: 500.1 GB, 500107862016 bytes

255 heads, 63 sectors/track, 60801 cylinders, total 976773168 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 4096 bytes

I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk identifier: 0xebe440c1

   Device Boot      Start         End      Blocks   Id  System

/dev/sda1              63       80324       40131   de  Dell Utility

Partition 1 does not start on physical sector boundary.

/dev/sda2   *       80392      158520       39064+  83  Linux

/dev/sda3   *      158584    78283584    39062500+   7  HPFS/NTFS

/dev/sda4        78283592   976773167   449244788    5  Extended

/dev/sda5        78285640   117348144    19531252+  82  Linux swap / Solaris

/dev/sda6       117350400   166178520    24414060+  83  Linux

/dev/sda7       166180864   215008992    24414064+  83  Linux

/dev/sda8       215011328   244308200    14648436+  83  Linux

/dev/sda9       244312064   263843312     9765624+  83  Linux

/dev/sda10      263845888   283377144     9765628+  83  Linux

/dev/sda11      283379712   367364088    41992188+  83  Linux

/dev/sda12      367366144   976773167   304703512   83  Linux

Which is pretty good. Am now installing windows in /dev/sda3 and once that is done will continue with my gentoo installation.

Cheers,

jim

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