Re: [Testbed-admins] Booting error in Customizing the Generic Image

["'Ryan Jackson'" <rdjackso@flux.utah.edu>]

* Cheng Cui <ccui1@tigers.lsu.edu> [091113 17:31]:
> It looks I got the reason. The whole-disk image (BSD+linux.ndz) must be
> copied into disk first, then, any separate images can be copied into the
> disk and they work. I tested it by reformat my hard disk, then, a
> separate image copy does not work, but once the whole disk image copy is
> committed, the following separated copy could work. Please refer to my
> attached file on detail.

I would not expect separate images to work if you've reformatted the
disk in some way.  Doing so would wipe out the partition table.  As
long as you have a valid partition table in place then separate images
will work.

I looked at the errors in your previous email again, and I think I
figured out what happened.  Somehow your partition table was corrupted
and when you loaded the FreeBSD image it overwrote the sector
containing the partition table.  Once you ran hdparm, it re-read the
table and saw the first sector of the FreeBSD partition.

Essentially, this sector contains a DOS partition table with one
partition (number 4) of type 0xa5 (FreeBSD).  This was created by the
FreeBSD bootloader installer for compatibility reasons.  This is why
Linux saw the partition /dev/sda4.  However, it did not add any of the
BSD partitions inside it because for some reason this 'fake'
partition's size doesn't match up with the real total size of the BSD
partitions (or something similar).

Anyway, as long as your partition table is valid single-partition
images should work just fine.

Thanks for getting back to me so quickly on this.