What happens if you copy a file from one disk to another, using the same file path?

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I know that you should never copy/move between disks and user shares (e.g. from /mnt/disk1/Share1/File1 to /mnt/user/Share1/whatever/File1), but I'm wondering about moving (i.e. copy, then delete) files from one disk to another.  For important files like personal photos, I prefer to copy, then compare checksums, then delete the source (rather than just use `mv`). 


If I copy a file as follows, what happens?  (assuming I have a share "Photos" with both those disks included)


SRC:  /mnt/disk1/Photos/Pic1.jpg

DST:  /mnt/disk2/Photos/Pic1.jpg


Now you have 2 versions of the same file in 'identical' locations within the Share.  Is this a situation that should be avoided?  What exactly happens?

Edited by nukem492
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1 minute ago, trurl said:

The file from the lowest numbered disk is the one that shows up in the Photos user share. No problems otherwise.

So I don't have to worry about overwriting random file data or parity data in this situation?  I guess the Parity is being updated when this file transaction occurs, but it would be a legitimate parity update, right (i.e. both files would be 'protected' by my parity)?

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Any write operation on any array data disk updates parity. Parity wouldn't be valid otherwise. And anything that is not strictly a read operation is a write operation. For example

16 minutes ago, nukem492 said:

then delete the source

also updates parity since delete is a write operation.

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