Is parity maintained when moving files from one disk to another within the array?

[var]

Hi!

 

I used the unBALANCED plugin to move files of one the disks in the array and the process was interrupted in the middle. Lot of files were duplicated. I am removing these files manually from the command line.

 

I am wondering if I move/update/delete files from the disks on the array from the command line (GUI, etc.) is that parity on the parity disk(s) maintained?

 

Do I need to run a parity rebuild after I have moved/updated/deleted files within the array?

 

The docs at https://wiki.unraid.net/Transferring_Files_Within_the_unRAID_Server do not mention any information on parity. I have also searched the forums and searched the internet and I was unable to locate information on parity updates. Can the docs also be updated so it is clear what happens when data is moved between disks in an array.

 

Thanks!

[Squid]

45 minutes ago, var said:

I am wondering if I move/update/delete files from the disks on the array from the command line (GUI, etc.) is that parity on the parity disk(s) maintained?

 

Yes

[sota]

Someone can correct me if i'm wrong, but the only time parity isn't maintained is if the array is inactive, and you mount the disks outside of the array.

[Squid]

That's correct, but is also something that pretty much you would never do (nor is there any real reason to ever do it)

[var]

Thank you both @Squid! and @sota!

 

To complete my understanding there is a process on the server that is monitoring all updates (writes and deletes in case of a move) and updating the parity disk(s)?

[Squid]

Yes in real time.

[var]

Thank you!

[var]

Hi Squid,

 

I have read through the Parity docs at https://wiki.unraid.net/index.php/Parity. Is there another section in the doc that gives a high level explanation of the implementation. It would satisfy my curiosity to know the implementation details of Parity process.

 

Thanks!

[itimpi]

Not sure there is a description of the sort you mention you mention.  There is also,a,bit about parity in the ‘Getting ‘started’ section of the online documentation but that is probably at the same level,as,the link you mention.  The source of the md driver that implements parity at the LInux level in Unraid is provided with Unraid but that would be rather hard to,peruse.   You will probably just have to,ask,questions to clarify any point that you think needs it.  

[var]

Thank you @itimpi! My understanding is getting better as I use, explore, read the docs and get answers to the questions. Thank you to everyone that replied on this thread, it immensely helped me to get a better understanding of the workings of Unraid. This builds my confidence and allows me to do operations on the array without worries.