Sometimes things go wrong and you might have to extract files manually on your media tank.
As not everyone knows how to do this I will describe what I did.
Be aware that this is a slow process (up to an hour for 5 GB, depending on the compression ratio.

This is command will extract a .rar file in the same folder:

/mnt/syb8634/bin/unrar x filename.rar

I’ve done this using telnet but SSH should work too.

This implies that root becomes owner of your files. You won’t be able to move them with the nmt user (e.g. using SMB) and you’ll encounter other issues.

Solve this by changing the owner of the files:

chown nmt *

Then change the group:

chgrp nmt *

Then change the access rights:

mach zehnder modulatorchmod 666 *

Note: I know that 666 isn’t exactly the most secure option but all the other files on the NMT are world rw-able so I’m not going to change this.