How many copies best for Duplication

[BG1]

I have 3 large spinners and 2 X 2T M2's set up in my pool. I could easily use 4X duplication, but I'm currently balancing for for3 in the hope that each copy is on at least on its own drive.

What would be best to preserve and protect my stuff, file or folder duplication and 2 or 3 or 4 times duplication?

Thanks

[Christopher (Drashna)]

There isn't a good answer  for this, and it varies from person to person.  

I would recommend x2, normally, and x3 for anything that is especially important and you cannot lose. (and copy that stuff elsewhere, such as to the cloud).

[BG1]

Thanks for the reply.

I found I think new options in the later SW version and set DP for 3 duplications. It finished that overnight. 8 hours later I have a message saying a disk is missing.

It's one of the 2 M2's I added yesterday.

When I try identifying there is no result - but you can see that there is a drive available to add which is the subject NVME but the identification is shortened and its now marked unallocated.  Status of duplication is unclear since its all grey now.

It's now a dilemma how to proceed. I can't read the drive and I suppose that any next step will destroy the data. Perhaps its duplicated, but maybe not.

Would you care to provide me guidance - thanks.

[britgeezer]

Thankfully Drive Pool did its job, and I was able to remove the suspect M2 SSD without losing data.

It was a completely new failure to me.

[Christopher (Drashna)]

The NVMe drive completely failed? If so, I'm sorry to hear that!

As for the pool, yeah, once you remove the missing drive, it will remeasure the pool, and then run a duplication pass, reduplicating any of the data that needs it.