Maximum disk sizes

For the NV+ & Duo (and other sparc-based units), it's currently 2 TB. For the Ultra/Pro x86-based units, it's 3 TB. The primary reason is that the sparc-based units only support MBR disks, while the newer Ultra & Pro units support GPT. Not sure if the sparc units will ever support GPT, as Debian has ceased development on sparc-based platforms.

You can read up on the GPT vs. MBR issue here: http://www.burnedin.com/article/gpt-vs-mbr-explained

At the beginning of every hard drive there is a designated portion called the MBR (Master Boot Record). The MBR gives your system information about the drive and if/where to run your installed operating systems. Some of this information reveals details about the size and partitions on the drive. It's a method that has worked well for years, but the MBR is starting to become outdated since it can only hold enough information to define partitions on drives less than 2.2TB in size. This is where GPT steps in. As it turns out, GPT is becoming an option out of necessity because of those size limitations of the MBR. Currently we are on the cusp of regularly pumping out hard drives larger than 2TB and we need this new partition format option so that users can use every bit of space on their huge drives. Basically, GPT reserves a portion of the hard drive, in addition to the part reserved for the MBR. GPT uses this extra space to store even more information about the hard drive and its partitions. This allows for hard drive sizes of ridiculous proportions. How large? Try 9.4ZB, or Zeta-bytes,which (if you're nerdy and really care) is 20 zeros after the "94." Basically, hard drives will be non-existent by the time we need storage that large.