I have a Mac Pro and run OSX 10.6.4. I have a Drobo with a 4x1TB single partition, max capacity of 16TB, and 1.19TB Used and 1.50 TB Free. I backup the four internal HDD (excluding iMovie Events, etc) to Time Machine on Drobo which is the only current use. However, I bought a new HD camcorder and realize I will need some external storage, since these files are HUGE.
It seems to me I should add 2-3 x 2TB HDDs to Drobo to get a good current capacity for both Time Machine and for storing my video files. In addition, I am thinking it would work best with two partitions. Is this recommended and can I do so without losing my Time Machine backups? How?