Odd # of sectors in partition

Odd # of sectors in partition

Post by Kenneth Ste » Thu, 14 Jul 1994 09:17:34

'fdisk' is giving me the warning of "Odd number of sectors" in some of
my partitions. I have just re-installed Linux (slackware) after my
partitions became corrupt in my previous installation. I had the same
warnings then and am now wondering if this is what caused the corruption
in the first place.

        The partitions look as follows:
Disk /dev/hdb: 8 heads, 39 sectors, 762 cylinders
Units = sectors of 1 * 512 bytes

   Device Boot  Begin   Start     End  Blocks   Id  System
/dev/hdb1   *      39      39   30887   15424+  83  Linux native
/dev/hdb2       30888   30888   53663   11388   82  Linux swap
/dev/hdb3       53664   53664  237743   92040    5  Extended
/dev/hdb5       53665   53665  197183   71759+  83  Linux native
/dev/hdb6      197185  197185  237743   20279+  83  Linux native

        The '+' signs indicate the partitions with the odd number of
sectors. I have noticed that hdb5 and hdb6 do not start at the begining
of a cylinder. I cannot tell fdisk to start one sector back (53664 & 197184)
for some reason. If I move them up one sector (53666 & 197186), the '+'
goes away.

        Is the warning a problem? Should I move the sector Start address
up? Is there another way of setting them (perhaps with 'x' from within
fdisk (experts only))?

        Disk "b" is a 120M IDE and I have allocated the entire disk to
Linux. I start Linux from under OS/2's Boot Manager which is why the
first partition is off.

        I'd like some advice before I continue installing packages and
configuring the system.



1. Partition contains odd number of sectors.

  I'm receiving an unusual warning from Fdisk, while trying to set up
Slackware Linux on a new, "clean" Western Digital Caviar 425M drive,
physically configured as a "slave", and will be /dev/hdb.  I've looked in
both the Installation Guide and HOWTO, and haven't seen anything about it.

  First, the drive's CMOS parameters--straight from the manual--are:

  Cylinders       Heads      Sectors/Track        WP/LZ    
    1023           14            58                1023

  Now, I run Fdisk for a new, primary partition.  My responses and the
warning follow:

Partition number:           1
First cylinder(1-1023):     1
Last cylinder..:            +300M
Warning:  partition 1 has an odd number of sectors.

When I list the partition table, another warning appears under 1's

Partition 1 does not start on cylinder boundry:
phys=(0,0,2) should be (0,1,1)

I should note that I set up a second primary partition, and it went smooth
as could be.  So, I'm thinking that it may have something to do with needing
a boot sector.

Any ideas/comments would be most welcome. Thanks..


*Home:                        **Work:                             *
*#310, 1445 W. Jessamine Ave. **Kavouras, Inc. Computer Ops.      *
*St. Paul, MN  55108          **6301 34th Street, South           *
*                             **Minneapolis, MN 55450             *
*     Email: When it absolutely positively has to get lost at the *
*            speed of light.                                      *

2. Killing all processes started by a pid

3. fdisk complains about odd number of sectors

4. Config Help

5. fdisk: "partition <x> does not end on partition boundary" -- 64 head/32 sector v. 255 head/63 sector conflict?

6. 101945-42

7. sector-by-sector copy of while drive?

8. mounting iso image in C/C++

9. write sector by sector...

10. Can I get the information of disk such as bytes/sector, sectors/track, tracks/cylinder?

11. how do I disk copy sector by sector

12. How do I fix a corrupt partition sector?

13. Why does the OpenBSD partition start at sector 63?