why does the installer change the partition table?

[Rashkae]

Thufir wrote:
> On Wed, 31 Dec 2008 17:36:32 +0800, Koh Choon Lin wrote:
> 
>>> The partition tables of the following devices are changed:
>>>  SCSI1 (0,0,0) (sda)
>>>  SCSI1 (0,1,0) (sdb)
>>>
>>> The following partitions are going to be formatted:
>>>  partition #5 of SCSI1 (0,0,0) (sda) as swap partition #5 of SCSI1
>>>  (0,1,0) (sdb) as swap
>>>
>>> which concern me because I don't want to lose data on sda but don't
>>> want to back up (lotsa cd burning) at the moment.
>>>
>>> I tried the manual approach, selected which sdb partitions I wanted
>>> effected, but keep getting that message that the partition table for
>>> sda has been changed.  If so, I didn't intentionally change it :(
>> Are you trying to install the boot loader in sda and the rest of the
>> system on sdb?
> 
> 
> Maybe your question explains why sda is being touched at all.  The 
> bootloader on sda needs to be changed, perhaps?
> 
> I want to do a clean install onto the already partitioned sdb and leave 
> sda entirely alone.  At a later point I'll back up sda (laborious) and 
> reformat it for extra storage.

Easy as pie then.

Disconnect the drive you want to preserve, install Ubuntu.  When you
have  working Ubuntu system, re-connect the original hard drive.  If
needed, tell your bios to boot from the other hard drive (where you just
fresh installed Ubuntu)