Delete files securely on Linux – Journaled file systems - Comment Page: 1
Few days ago I write about shred, which work fine for old systems, like EXT2, but not so nice with journaled file systems. Modern file systems need something more robust, like dd and srm (a secure replacement for rm). Unlike the standard rm, srm overwrites and rename the files before unlinking them. This makes it very hard to recovery of the data.
Create test file:
echo "secure content" > /tmp/secure.txt
dd and srm command usage
Fill free space with zeroes (Use very carefully):
dd if=/dev/zero of=/tmp/secure.txt
Write buffered data from the memory out to disk
sync
Delete file with srm:
# Basic example
srm /tmp/secure.txt
# US Dod compliant 7-pass...
How does srm, properly overcome the issues faced with a Journaling file system? Is this why you run the sync command?
Thanks!
Kenneth
Hi Kenneth,
This guide does not provide absolutely secure way to remove files, I think that the only totally secure way to delete files permanently is overwrite whole disk, but this makes it harder to recover data. Sync command is used to flush file system buffers.