‘Use 100%’ – But there is space left!

lrg tango drive hard disk Use 100%   But there is space left!It just happened that a md device appeared as out of storage space.

df displayed the following:


Calculative there is something wrong because there are still 0,4T left. This is because ext reserves 5% of space per default because you would not be able to login in if there not enough space on the filesystem and you wont be able to enter the rescuing rm command. For my md device, which does not contain any systemfiles there is no need to reserve any space :

Sets the reserve to 0% and the 0,4T are free for usage.