Spoiler Alert: I don't know a ton about what I'm doing, but I've been tasked with data protection and backing up at my workplace so I installed a NAS and set it up. Ideally I'd like to not have to think about it all the time, and that means getting a lot of storage so I don't need to frequently replace the drives. SO I set up the storage pool to be the majority of the space and when I did that I got a warning that the volume should not be more than 80% of the pool. why is this? I changed that warning threshold to be 95% so I don't have to see any warning text, but I am wondering why 20% of the space is recommended to be reserved by default.
Thank you