How to check if it's a PReP partition

[Paulo Flabiano Smorigo]

Hi,

How can I know if a partition is securely a PReP partition? Besides  
check the partition type (41), is there another test that I can do to  
confirm that?

At the page bellow are two other codes used for the same code of PReP (41):

http://www.win.tue.nl/~aeb/partitions/partition_types-1.html

41 Linux/MINIX (sharing disk with DRDOS)
41 Personal RISC Boot
41 PPC PReP (Power PC Reference Platform) Boot

What kind of checks can I do? Can I use the partition size or if it's  
the first of the disk as parameters to check it?

Thanks,

Paulo Flabiano Smorigo
Linux Technology Center Brazil Software Engineer
IBM Systems & Technology Group

On Thu, Oct 20, 2011 at 03:05:51PM -0400, Paulo Flabiano Smorigo wrote:
> How can I know if a partition is securely a PReP partition? Besides
> check the partition type (41), is there another test that I can do
> to confirm that?
>
> At the page bellow are two other codes used for the same code of PReP (41):
>
> http://www.win.tue.nl/~aeb/partitions/partition_types-1.html
>
> 41 Linux/MINIX (sharing disk with DRDOS)
> 41 Personal RISC Boot
> 41 PPC PReP (Power PC Reference Platform) Boot
>
> What kind of checks can I do? Can I use the partition size or if
> it's the first of the disk as parameters to check it?

I don't believe there is anything you can do.

The contents can be anything (mine contains the raw grub image for
booting).

rceng03:~# file -s /dev/sda1
/dev/sda1: ELF 32-bit MSB executable, PowerPC or cisco 4500, version 1 (SYSV), statically linked, stripped

Perhaps you can check if it contains executable code, since that is
certainly true of how the partition is used by IBM.  I imagine that
would not be true of the linux/minix one (unless I suppose the bootloader
happens to be embedded at the start of the partition in a non raw way.
I believe x86 uses raw executeable code in that case, unlike PReP which
seems to have ELF binaries instead).  No idea about Personal RISC Boot.

rceng03:~# parted /dev/sda print
Model: IBM ST3146356SS (scsi)
Disk /dev/sda: 147GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number  Start   End     Size    Type     File system  Flags
 1      32.3kB  8225kB  8193kB  primary               boot, prep
 2      8389kB  1009MB  1000MB  primary               raid
 3      1009MB  141GB   140GB   primary               raid
 4      141GB   147GB   5806MB  primary               raid

rceng03:~# parted /dev/sdb print
Model: IBM ST3146356SS (scsi)
Disk /dev/sdb: 147GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number  Start   End     Size    Type     File system  Flags
 1      32.3kB  8225kB  8193kB  primary               boot, prep
 2      8389kB  1009MB  1000MB  primary               raid
 3      1009MB  141GB   140GB   primary               raid
 4      141GB   147GB   5806MB  primary               raid

Mine happens to be partition one, but I think that is just because if
habit on my part.

I think the size of 8MiB in my case is simply the minimum for one
cylinder.