In this scenario you are the Systems Administrator for a healthcare company. Your manager has tasked you with logging into the fileserver running CentOS Linux 7.7 and securely deleting some sensitive patient data, ensuring that it cannot be easily recovered. No other files should be altered.
Learning Objectives
Successfully complete this lab by achieving the following learning objectives:
- Confirm File Is Readable
Confirm the size and permissions of the file:
[cloud_user@$host]$ sudo ls -l /mnt/patient.1Show the contents of the file:
[cloud_user@$host]$ sudo cat /mnt/patient.1- Fill Free Space
Be sure to double check the path, as this command does no error checking and will overwrite data:
[cloud_user@$host]$ sudo dd if=/dev/urandom of=/mnt/junk status=progress; sync- Overwrite File
The
shredcommand is the simplest method. Specifying-xensures that the filesize remains unchanged:[cloud_user@$host]$ sudo shred -x /mnt/patient.1If the
shredcommand is not available, we can use the followingddcommand:[cloud_user@$host]$ sudo dd if=/dev/urandom of=/mnt/patient.1 bs=45 count=1 iflag=fullblock status=progress- Confirm File Was Overwritten and Remove
Show file contents:
[cloud_user@$host]$ sudo cat /mnt/patient.1Remove file:
[cloud_user@$host]$ sudo rm /mnt/patient.1- Restore Free Space
Remove junk file:
[cloud_user@$host]$ sudo rm /mnt/junk
