Operating system cannot boot from > 2TB array
Problem:
After installing the operating system, the system is unable to boot from the array.
Details:
GRUB only recognizes msdos partition tables. Since msdos partitions are limited to 2TB in size, it is not possible to directly boot from a > 2TB array.
Workarounds:
To work around this, you can enable a feature in the 3Ware BIOS called 'autocarving'. This will split the array into multiple 2TB volumes (/dev/sda, /dev/sdb, etc). The BIOS of newer controllers also support the option to create a small boot volume (/dev/sda) and then allocate the rest of the array to a single large partition. The following 3Ware knowlegebase article has more information: