i am new to encrypted disks and so forth.
i have a new kubuntu 12.10 install i have setup with an encrypted volume.
i am trying to backup the binary luks header file as a first exercise working with my encrypted disk. this is the command line i used...
alonzo@eartha:~$ cryptsetup luksHeaderBackup --header-backup-file ./backup1 /dev/sda1
WARNING!!! Possibly insecure memory. Are you root?
Cannot open device /dev/sda1 for read-only access.
if i put an sudo in front of this will it back up my luks header for /dev/sda1 into backup1?
after reading dm-crypt FAQ i am feeling cautious.
also what is "Possibly insecure memory." about?