I understand that for the drives that the ZFS is on, it's best that they are all the same size, same drive type. I also understand that the number of physical disks in a ZFS array cannot be dynamically changed. For example, start with 3 physical drives, 3 drives is what it is now and forever more.
However, budget won't support that now. Can I use different size drives as 'placeholders' until such time as I can get proper drives?
I've got a case I can put 5 drives in.
I have two 2TB drives on the way. I also have two 1.5 TB drives and one 1.0TB drive that I can use, so five drives would be:
2 ea 2TB
2 ea 1.5TB
1 ea 1.0TB
The idea is to set up the ZFS pool with these, then each month order another 2TB drive and replace a drive until all five physical drives are 2TB drives.
Is this reasonable? Or am I not understanding how things actually work?