I am considering getting a new Time Capsule (2TB) as a basic/pseudo NAS, in addition to a target for Time Machine for two macs.
My macs each have a 500 GB ssd. Neither are currently even half full, but at some point down the road, I assume they'll each have 400 GB. I think I've read that Time Machine should have storage for at least 1.5x the amount of data being backed up, so 400 x 1.5 = 600, x2 macs = 1.2 TB needed.
With the 2 TB Time Capsule, I'd have 800 GB available for NAS, but I need to LIMIT the space used by Time Machine, since it otherwise continues to grow, using all available space on the disk. But the TC disk can't be easily partitioned, so the solution I found is to put my NAS files in a blank Disk Image on the Time Capsule -- which prevents Time Machine from using that space. (See Can I set up quotas on my Time Capsule?)
When creating a Disk Image in Disk Utility, the largest preset is 8.3 GB. But this would require an 800 GB Disk Image. So finally, my question...
QUESTION -- Is an 800 GB Disk Image (and this strategy in general) ok, or is it a very bad idea? Why?