Disk wiping recommendations

[Dazed_75]

please be careful if you really want a secure wipe.  Use a real
multipass tool (such as DBAN and others) for doing a secure wipe.
Those single pass simple techniques like dd prevent common utilities
from being able to see the old data but are really not secure from
better forensic techniques.  Adequate if the data is not really
critical, but inadequate for important stuff.