Advice on optimum reconfiguration procedure

[CaptainTivo]

Hello,

I am getting ready to do a major reconfig on my Unraid server and I thought I would solicit opinions on the optimal way to do it.

I currently have 13 disks (including parity and cache) which max out my SATA ports.

Many of the disks are smaller (2, 3 and 4 TB) that I wish to replace with larger drives.

Here is the current setup: 

1 10 TB parity disk

2 2 TB disk

3 3 TB disk

2 4 TB disks

1 8 TB disk

1 500 MB ssd (cache)

I intend to remove 2 2 TB, 3 3 TB and 1 4 TB drives (6 drives) for a total of 17 TB ( I will leave the data on them (movies, TV shows) as a kind of dead storage archive.

I will replace the 10 TB parity with 12 TB disk and re-use the old parity disk and add a single new 8 TB drive.

The remaining drives have enough storage to hold everything (for now :-)

 

The question is, what order to remove/add the drives is optimal?  I mean, I have to remove at least one drive to even put the new 8 TB drive into the array.

 

I could: (below, drives to be removed and archived are called "target" drives.

1) copy data from one of the target drives to empty space in the array

2) remove the target drive and use it's SATA port to put in the new 8 TB drive and

3) rebuild parity

4) then copy all the remaining data from the rest of the target drives (I will have enough free space after adding the new 8 TB drive)

5) remove all the target drives and put the new parity drive in the server

6) rebuild parity (again) and

7) pre-clear the new 12 TB parity drive

8-) remove the old 10 TB, install the new 12 TB parity drive

9) rebuild parity

10) pre-clear the old parity drive

11) add it to array

12) rebuild parity yet again

 

Is there a more efficient way to accomplish this without rebuilding parity 4 times?

 

Thanks in advance for any help.

 

 

[testdasi]

It depends on how risk averse you are.

The fastest way requires that you are comfortable with being temporarily unprotected.

1. Start new config (Tools -> New Config), and reassign all disks + assign the 10TB as a data disk (i.e. no parity i.e. not protected). The 10TB is likely to require to be formatted.
2. Copy the content of each to-be-removed small HDD over to the 10TB and the existing 8TB. (since you said 1 new 8TB gives you sufficient space to do that, 1 new 10TB should definitely give you sufficient space). This should be faster due to no parity but don't do multiple parallel writes to the same HDD.
3. Verify everything is copied correctly and remove the small HDDs and connect the new 12TB + new 8TB
4. Start new config and reassign the old 8TB + 10TB as data. Preclear the new 12TB + new 8TB.
5. Once preclear is done, assuming no error, stop array, assign new 12TB to parity and new 8TB to data. Parity should be rebuilt automatically when array starts.

Edited March 5, 2020 by testdasi