At 01:34 PM 9/14/2020, you wrote: >what if you just dd the first 1GB of the disk and the last GB of the disk >(the last because of RAID signatures of some controllers that write to the >end of the disk) >Look at this article and modify accordingly >https://zedt.eu/tech/linux/using-dd-to-repeatedly-erase-a-specific-range-of-sectors-on-the-hard-disk/ > >Also, use wipefs -a (Gordon Messmer answered faster than me) > >On Mon, Sep 14, 2020 at 3:18 PM david <david at daku.org> wrote: > > > Folks > > > > I've encountered situations where I want to reuse a hard-drive. I do > > not want to preserve anything on the drive, and I'm not concerned > > about 'securely erasing' old content. I just want to be able to > > define it as an Physical Volume (in a logical volume set), or make it > > a ZFS disk, or sometimes make it a simple EXT3, ExFAT or NTFS > > disk. However, old 'signatures' get in the way and Linux sometimes > > refuses to let me proceed. I know that a fool-proof solution is to > > use the "dd if=/dev/zero bs=32768 oflag=direct" on the disk, but when > > we're talking USB-connected hard drives of 8 TB, that's an operation > > that can take days. > > > > The disk in question might even have been corrupted. This would make > > using 'zpool destroy' to clear out a ZFS disk, or > > > > I've tried erasing the first megabyte of the disk, but there are ZFS > > or LVM structures that get in the way. So, does anyone have an > > efficient way to erase structures from a disk such that it can be reused? > > > > Something like > > -erase first N blocks (block defined as 4096) > > - Erase <number> blocks starting at block <number> > > - erase last <number> blocks > > > > At least such an algorithm would be quicker than erasing 8 TB of data. > > > > David > > > > _______________________________________________ > > CentOS mailing list > > CentOS at centos.org > > https://lists.centos.org/mailman/listinfo/centos > > Thanks for the suggestion. "wipefs" looks like the right answer. David