freenas rsync failed with exit code 11

[Lumarico]

I have recently decided to try out Freenas switching from using ubuntu server 16, but have come across a problem when trying to import a drive without loosing any of its data, but i get the following error,

rsync failed with exit code 11

Error: Traceback (most recent call last):
File "/usr/local/lib/python3.6/site-packages/middlewared/job.py", line 332, in run
await self.future
File "/usr/local/lib/python3.6/site-packages/middlewared/job.py", line 363, in __run_body
rv = await self.method(*([self] + args))
File "/usr/local/lib/python3.6/site-packages/middlewared/schema.py", line 664, in nf
return await f(*args, **kwargs)
File "/usr/local/lib/python3.6/site-packages/middlewared/plugins/pool.py", line 488, in import_disk
raise Exception("rsync failed with exit code %r" % rsync_proc.returncode)
Exception: rsync failed with exit code 11

I have no idea what i means as it does this once the import reaches around 34%

the drive is a 3tb WD Red

 

[Fredda]

man rsync:

Code:

EXIT VALUES
       0      Success
       1      Syntax or usage error
       2      Protocol incompatibility
       3      Errors selecting input/output files, dirs
       4      Requested  action  not  supported: an attempt was made to manipulate 64-bit files on a platform that cannot support them; or an option was specified
              that is supported by the client and not by the server.
       5      Error starting client-server protocol
       6      Daemon unable to append to log-file
       10     Error in socket I/O
       11     Error in file I/O
       12     Error in rsync protocol data stream
       13     Errors with program diagnostics
       14     Error in IPC code
       20     Received SIGUSR1 or SIGINT

Most probably an error on one of the disks. I recommend to run a long smart test on all involved disks.