Hey everyone, 

Quick question, in my three array disks I have the third disk that is not being utilized. I am about to add another disk to the array but am concerned that the data is not being spread with my existing disks. I do not have any disks excluded in my share definitions. 

 

Any help understanding how data is spread among the disks in the array is appreciated. 

 

Thanks. 

It will when you pass 1.5TB used on disk2.

 

https://lime-technology.com/wiki/index.php/Un-Official_UnRAID_Manual#High_Water

Edited May 2, 20179 yr by johnnie.black

Great, thanks!

 

I bought a new 4TB drive. Based on what you are sharing should I wait to add it to the array until the third disk is a bit more full? That way I reduce wear and tear?

Or changing allocation to Most Free would start writing to the new disk until the free space gets to another disks free space then it will start writing between them 

2 hours ago, graywolf said:

Or changing allocation to Most Free would start writing to the new disk until the free space gets to another disks free space then it will start writing between them 

But I recommend sticking with High Water. It is a good compromise between spreading your usage, without the need to constantly switch disks. And High Water by itself can effectively do most of the work that you would get from specifying Split Levels, since it will likely keep things together when they are written together.

 

The other choice is Fill Up. Whatever you choose, be sure to set the Minimum Free. It should be set to be larger than the largest file you ever expect to write. unRAID will use a disk if it has more than the minimum free space, and it will choose a different disk if it has less. If unRAID starts to write a file, and the disk fills up before it is finished, then the write will fail.

 

I usually think it's best to not add drives until you need them. More drives just means more things that can have problems. Also, if you wait to buy a drive until you need it you may get a better price. But since you already bought it you will also want to consider the ticking warranty clock.

 

Another possibility would be to use the new 4TB to upsize the existing 2TB.

I bought it because I will have a busy summer of photography  High water sounds good.

 

The thought of having a spare and not using it until it's needed or swapping it out for the 2GB drive. 

 

If I decide to pull the 2GB drive, do I simply exclude it, run the mover and pull it?

35 minutes ago, Kash76 said:

If I decide to pull the 2GB drive, do I simply exclude it, run the mover and pull it?

I was suggesting replacing it with the 4TB. If you replace the 2TB with the 4TB unRAID will rebuild the 2TB onto the 4TB, and parity will remain valid.

 

If you simply remove the 2TB, you will have to set a New Config without it and rebuild parity.

 

From your screenshot, it looks like the 2TB may not have any files on it, but if it does, you would have to move them yourself.

No files there so yeah, I can rebuild it in place.

 

Thanks!

Edited May 2, 20179 yr by Kash76

5 minutes ago, Kash76 said:

No files there so yeah, I can rebuild it in place.

You could rebuild it even if it did have files on it, that is the whole point of rebuilds, to get the filesystem and all its contents onto the new disk. And even without files, it still has a filesystem, which is included in parity, so a rebuild is appropriate.

Yes, good point. Thanks again!