What does it mean exactly in Array Operation option "Read-Check"

[poprawka]

I only have one 4tb disk and I clicked "check".

This option is used to check the disk for possible errors? or Is it to check the read speed in each sector? Should I use it e.g. once a week / month ?

If it is used for something else, please explain.

[itimpi]

Basically this just tries to read every sector on your disks to see if they can be read without error.

[trurl]

20 minutes ago, poprawka said:

one 4tb disk

Assuming you mean you don't have a parity disk, it is checking that it can read every bit of the disk.

 

Seems to me that regular extended SMART test would be more useful.

[poprawka]

36 minutes ago, trurl said:

Assuming you mean you don't have a parity disk, it is checking that it can read every bit of the disk.

yes, but I just bought another 4tb drive, one of these drives will be a parity drive...
Does that change anything in this test ?

[trurl]

2 hours ago, poprawka said:

one of these drives will be a parity drive...

So at some unspecified time in the future you will have a parity disk assigned to the array. Seems obvious that future situation doesn't apply to the current situation.

 

 

[poprawka]

7 hours ago, trurl said:

So at some unspecified time in the future you will have a parity disk assigned to the array. Seems obvious that future situation doesn't apply to the current situation

Yes.

Therefore, I am asking if I have already  2 x 4TB disks and one of them will be a disk parity.

Then... an option "Read-Check" doing something else? Is it used for something else?

 

[itimpi]

When you have a parity disk installed you will instead get a parity check.   In principle this involves reading a sector of every data drive, calculating what should be on the parity drive for that sector and then reading the sector off the parity drive to check that it has the expected value.