Media unrecoverable

[Ergi]

Hi all,
We are on FreeNAS-9-10.1 and MAc Pros 10.12. Occasionally we see a few errors when we copy/move folder in the server. Last night we did big copy of 9TB using Carbon Copy Cloner and we got this error "This file or folder is sitting on a bad section of hard disk media and is unrecoverable"
The media is fine and still accessible though. There was no other activity happening in the server.

 

[Glorious1]

That sounds like a strange warning to be getting from macOS or from CCC (which was it?). When you say the "media is fine", do you mean all the files and folders are there and accessible?

I wonder if you burned in the drives before putting them in a pool and loading them with data? Always good practice to make sure the disks are OK.

Did your big copy take place over wifi or ethernet? For such a big transfer I would always use ethernet.