Array of 30 Disks, swapping 7 with 7 new disks.

[Senect]

Hi, I searched around but I couldn't find a clear detailed procedure on how to do a massive swap, I have 30 drives on my UnRaid, I need to swap 7 of them with 7 newer larger disks, I need to know how to do a pre-clean of the disks on another PC (software to use and what to check) and how do I swap all of them togheter after the pre-clean is successful, I tried in the past to swap 2 disk, but I did it 1 at the time following the standard procedure, but it takes 2 days to do a parity check, and doing a parity check for each new drive will destroy all the others.
So if anyone can please explain in details the steps, software, procedure to do a massive swap like this let me know.

P.S. The 7 drive to swap out are 7x SAS 4kn 12TB, I need to swap them with 7x SATA 18TB, all the other drives in the array are SATA not 4kn, so I don't know if this should be taken into consideration or change the procedure.
I have 2 parity of 18TB HDD.

Thanks.

[itimpi]

You do not mention if you want to keep the data on the existing drives?

 

Note that you do not need to Preclear the drives unless you want to do this as a confidence test on the drives.   You could always run the extended SMART test on another machine as an alternative to a Preclear if you do want to test them.

 

[Senect]

1 hour ago, itimpi said:

You do not mention if you want to keep the data on the existing drives?

 

Note that you do not need to Preclear the drives unless you want to do this as a confidence test on the drives.   You could always run the extended SMART test on another machine as an alternative to a Preclear if you do want to test them.

 

Thanks for the reply, I want to keep the data of actual 7x12TB disks inside the array.
What can I use to do an extended S.M.A.R.T test on a w10 machine with the 7 new 18TB HDDs? I want to be sure they are working correctly and they are not defective, before moving data from the old disk to the new disk, and adding them to the array.

[itimpi]

2 hours ago, Senect said:

What can I use to do an extended S.M.A.R.T test on a w10 machine with the 7 new 18TB HDDs? I

You can normally use the manufacturers software.    There are also plenty of third party utilities such as DiskCheckup

[itimpi]

The safest way to proceed would be to  replace the array 2 at a time by rebuilding them (you can do 2 simultaneously with dual parity) as that way you always have the disk to be removed intact until the rebuild finishes and you are protected against other drives failing as you can revert to the previous position if needed.

 

Not sure there is any alternative approach that would be faster.

 

 

[Senect]

 

8 minutes ago, itimpi said:

The safest way to proceed would be to  replace the array 2 at a time by rebuilding them (you can do 2 simultaneously with dual parity) as that way you always have the disk to be removed intact until the rebuild finishes and you are protected against other drives failing as you can revert to the previous position if needed.

 

Not sure there is any alternative approach that would be faster.

 

 

Doing that will require building up parity 4 times, so it will take 8 days of constant activity + reading and writing constantly, it could cause other drive to die in the worst case scenario, but in the long run it will decrease the lifespan of all the other drives, there's another way to do this? for example cloning data using another machine on those 7 new drives, and then moving them all inside the UnRAID PC and doing only 1 parity check?

[itimpi]

33 minutes ago, Senect said:

 

Doing that will require building up parity 4 times, so it will take 8 days of constant activity + reading and writing constantly, it could cause other drive to die in the worst case scenario, but in the long run it will decrease the lifespan of all the other drives, there's another way to do this? for example cloning data using another machine on those 7 new drives, and then moving them all inside the UnRAID PC and doing only 1 parity check?

Note I am not talking about parity check, but about rebuilding the data drives.  All other ways I could think of involved LOTS of copying of data around and would be both risky and time consuming and probably even more demanding on the drives.    In practise a rebuild should not be that hard on the drives as it just involves reading (or writing) the sectors on each drive serially from start to end with minimal head movement.

[sota]

Honestly...

leave the array intact, copy the data from disk to disk as files, do that 7 times, swap 'em all out, and rebuild the parity drives. that'll put the least amount of stress on the rest of the disks.

[apandey]

5 hours ago, itimpi said:

In practise a rebuild should not be that hard on the drives as it just involves reading (or writing) the sectors on each drive serially from start to end with minimal head movement.

This is often overlooked / misunderstood. Sequential reads / writes are the simplest operation spinning drives can do, and doing it many times over is something the drive should be able to do easily without any detrimental effect. It's also reassuring that we know the drive can read fully - that's why we actually run routine scrubs and checks. If I suspect a drive will not be able to take a few full read/write cycles, I would be swapping it out

Edited April 12, 2023 by apandey

[Senect]

11 hours ago, sota said:

Honestly...

leave the array intact, copy the data from disk to disk as files, do that 7 times, swap 'em all out, and rebuild the parity drives. that'll put the least amount of stress on the rest of the disks.

How can I do this?
I have few empty slot on the server so I could technically add the drives as unassigned (never done that so I don't know if it could be done and how to do it) but if that can be done should I use binhex-krusader to copy from disk to disk, from the online array and the unassigned disk, for all of them, and after it's done remove the 7 old drives and add the 7 new one with the copied files, and do a parity check? Does this method actually works? because if it does I think it's the best way without stressing too much the parity by doing the rebuilt 4 times..

[sota]

that's exactly how I'd do it if I needed to upgrade to several bigger disks all at once.