The test is to image (with qemu-utils) the disk after any attempt;
‘qemu-img convert -c -p -O qcow2 /dev/sdX /somewhere/we/have/space/test.qcow2’
The resulting file should be ~197kB+ depending on device size.
If you see it blow past into MegaBytes then Ctrl-C, the disk is not forensically clean.
Many cases a simple blkdiscard will not clear the disk without a 100% zero write. If you're going to use the disk yourself you may not need ‘secure erase’.
‘qemu-img convert -c -p -O qcow2 /dev/sdX /somewhere/we/have/space/test.qcow2’
The resulting file should be ~197kB+ depending on device size.
If you see it blow past into MegaBytes then Ctrl-C, the disk is not forensically clean.
Many cases a simple blkdiscard will not clear the disk without a 100% zero write. If you're going to use the disk yourself you may not need ‘secure erase’.
Statistics: Posted by CwF — 2026-03-01 01:36