On 08/28/2010 06:31 AM, Robert Nichols wrote: > On 08/27/2010 11:53 PM, JD wrote: >> On 08/27/2010 09:25 PM, JD wrote: >>> Is there a Linux util to scrub free disk blocks and keep everything >>> else intact ?? >>> >> Someone (not on this list) described a simple way to do this. >> Scrubbing files to be deleted is easy enough - there are utils for it >> already. >> But scrubbing existing free space is slower and requires patience. >> >> cd to the root of the partition. >> sudo dd if=/dev/zero of=ZERO bs=20M >> >> When the dd program fails to write any further, you >> have grabbed and zeroed all available free disk blocks >> in the partition. >> >> Now all you do is use the command scrub to scrub the file ZERO >> and when done the file is deleted. > You need to do that as the UID permitted to use the reserved blocks > if you really want to clear _all_ the free space. Note that if the > drive has reallocated any bad sectors there could still be some old > data present on the disk. Guess you might call that caveat emptor. There is nothing you can do about relocated bad blocks. Perhaps there might be a util that can bypass the driver and send direct commands to the drive via a SATA port, or and IDE interface or a SCSI port, to write random data to the bad blocks - but such a util would have to be a standalone utility. Perhaps there is a boot disk out there with such a util. -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines