In-depth technology research: finding new ways to recover data, accessing firmware, writing programs, reading bits off the platter, recovering data from dust.
Forum rules
Please
do not post questions about data recovery cases here (use
this forum instead). This forum is for topics on finding new ways to recover data. Accessing firmware, writing programs, reading bits off the platter, recovering data from dust...
October 31st, 2011, 17:27
I work in a computer refurbishing center and I need to develop a fast efficient way to determine how I should destroy hard drive data.
The question I need to answer is: Should hard drive be wiped or crushed?
My policy is to crush any drive that has any errors reported during the wiping/verifying process.
The preferred method would be wiping so the drive can be reused or sold.
I'm trying to figure out how to answer this quickly; so hours of wiping time aren't wasted only to find out the drive has areas that can't be wiped or is otherwise unhealthy.
What SMART attribute limits should be used to identify a drive that should not be reused?
Is there any piece of hardware that can quickly and reliably test a hard drive?
Thanks for reading.
October 31st, 2011, 17:45
QUICKLY is an opinion : at maximum speed, a common 250GB takes not less than 40-50 min. and all this just to know that the drive still has problems.
Drives CAN be refurbished like BRAND NEW but this is a time consuming process and requires know how and equipment. This will sort out unusable drives and the ones that need downgrading (if not done by itself, it depends on model / brand). During this process all parameters are tuned and recalculated and data is erased completely - nobody on human scale can get data back after this. Drive is perfectly fixed, fast, error free and SMART cleared.
Usually, 70-90% or more of the drives can have a second life, regardless of SMART , errors , even firmware problems or non-catastrophical surface problems. But this depends on who does the job.
If you are interested , depending on number of drives per week you work, PM me with some details - maybe I can help.
October 31st, 2011, 20:05
@pwagner9999:
In addition to the refurbishment option explained by BlackST:
pwagner9999 wrote:I'm trying to figure out how to answer this quickly; so hours of wiping time aren't wasted only to find out the drive has areas that can't be wiped or is otherwise unhealthy.
In my experience, you can't know
with confidence the answer about whether wiping will be successful (within its expected limits) or not, without actually trying. Also, use of normal Write commands to wipe (overwrite) data, may not be an acceptable erasure technique to all customers.
There have been previous threads on the forum which you can search for, about the erasing of drives and the use of Secure Erase functionality and other methods, which you might find useful / interesting.
October 31st, 2011, 20:32
If you have a surplus of drives, won't miss any that get rejected, and want to minimize drives that you pass but turn out to be bad, I would first check SMART, fail any that have ANY reallocated/pending sectors, wipe the rest, then check SMART again and fail any with any reallocated/pending after wiping.
Of course this will fail some drives that might have been fine, and there are ways to do a better/more involved refurb job (that require indepth knowledge of the drives workings), but if you are limited to SMART and wipe tools this will minimize your headache. All my opinion of course, but that's how I'd do it.
November 1st, 2011, 10:06
I like that approach
drc - from what I can remember from several years ago, a similar algorithm is used by at least one of the commercial erasure products.
November 1st, 2011, 11:07
I just want to add that "Secure Erase" ATA Command is "NOT" secure.
November 1st, 2011, 13:00
... it is "secure" for common re-use...
November 1st, 2011, 13:27
Dangerous, I don't use it now. Even for common re-use.
November 1st, 2011, 15:09
AAAAAAAHHHHH... probably I know what you mean. Discussed in "separate see" , stay tuned please....
Powered by phpBB © phpBB Group.