[CentOS] Utility to zero unused blocks on disk

Mon Feb 8 21:34:48 UTC 2016
Wes James <comptekki at me.com>

Is there a utility to zero unused blocks on a disk?

CentOS 6.7/Ext4

I saw zerofree, but I’m not sure it would work on Ext4 or even work on this version of CentOS.

thanks,

-wes