I had the same question, but I think it's answered. I let Ubuntu erase the entire disk, but wasn't happy that it only created a root and swap parition. It seems prudent to at least have a data parition and keep the OS seperate.
and parted output is:
Just boot from the DVD, run gparted and shrink sdb1, make and format a new parition?
Code:
sudo fdisk -l
Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0009fd2e
Device Boot Start End Blocks Id System
/dev/sdb1 2048 1947758591 973878272 83 Linux
/dev/sdb2 1947760638 1953523711 2881537 5 Extended
/dev/sdb5 1947760640 1953523711 2881536 82 Linux swap / SolarisCode:
Disk /dev/sdb: 1000GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Number Start End Size Type File system Flags
1 1049kB 997GB 997GB primary ext4
2 997GB 1000GB 2951MB extended
5 997GB 1000GB 2951MB logical linux-swap(v1)