"dd" command runs when cinder deletes the volume
Hi team,
I noticed everytime when I delete the volume in openstack, the linux dd command was called, this also has been verified by the cinder volume log--
*bb9bf47774f9ba442f5b24c71077a - - -] Performing secure delete on volume: /dev/mapper/cinder--volumes-volume--d2ec2a30--f05a--4ea0--91cf--b6e5f7dcb241
2016-03-30 21:27:54.296 4166 INFO cinder.volume.utils [req-70f81ef1-4741-4307-b45c-b6127f741f84 d6cde2bd6c6c4b8c85dd98882d680741 c06bb9bf47774f9ba442f5b24c71077a - - -] Volume copy 20480.00 MB at 89.69 MB/s**
Although the system runs OK, anyway I am wondering why the dd was called, why there is a copy action during the volume deleting, could anyone explain? Thanks a lot.
Regards, para
It does to do a secure deletion, that means writting zeroes over your data to disable recovery under your volumes. This is a security concern to gain security against crackers and avoid data leakage.