Hi All,

 

I'm currently trying out unRAID on a spare PC with a plan to migrate to it from my current setup of ESXi with a few windows 10 VMs that currently do the job of my home server, etc. What I don't have is enough spare disks to migrate the approx 4TB of data (currently across 3 drives) to the new system in a single copy/paste, as I need to re-purpose the old disks into the new array. I do have at least 1 x 2TB drive that I can start the array with - possibly 2 x 2TB if I remove some redundancy from my existing setup.

 

My current server set up is a mixture of a mirrored and un-mirrored drives using DrivePool in a windows 10 VM. I've purchased a new 8TB drive to use as a dedicated backup with an incremental / differential backup plan (currently using acronis in a windows VM, but still TBC what I'm going to use when I migrate fully - I will probably keep the acronis going in a VM initially until I come up with a better solution), and will re-purpose my previous 4TB backup drive as the parity drive in unRAID.

So, I'm trying to work out the best way to do the migration without stressing the disks too much, or creating additional work; should I:

1. Create the array in unRAID without a parity drive initially and migrate the data and drives across one by one, then add the largest drive (4TB) as parity at the end? I'm thinking this would mean the system will only have to create the parity set once at the end, rather than having to re-compute it every time I add an additional drive as I gradually move across once the data has been copied across from the old system?
2. Add the parity drive and 1 or possibly 2 data drives, then gradually add more data drives as the disks are freed up from the old system when the data is copied across. This means the data will all be protected right from the start in unRAID, but will it be slow and put additional stress on the parity drive every time i add an additional disk?

Thanks in advance.

Either approach will work, but you seem to misunderstand how parity works when adding a new disk?  At that point Unraid ‘clears’ the disk (I.e. writes zeroes to every sector) as that leaves parity unaffected and thus the parity drive is not involved at all. 

6 minutes ago, itimpi said:

Either approach will work, but you seem to misunderstand how parity works when adding a new disk?  At that point Unraid ‘clears’ the disk (I.e. writes zeroes to every sector) as that leaves parity unaffected and thus the parity drive is not involved at all. 

Ah, of course - that makes sense. Thank you.

So actually, as I have a parity drive available, the better / safer option would be to go with my option 2, as the parity drive would be there and doesn't get any additional stress, and each drive joining the array gets wiped only once. Thanks again.