Formating a new hard drive

[Gubbi]

IMHO, full formatting is a waste of time.

Modern hard drives use massive redundancy to ensure data integrity. The platters themselves are not that reliable and it is only through error correcting codes that they even work. The health of a sector is measured by looking at the amount of errors recovered from when reading a sector. If the quality of a sector goes below a certain threshold it is remapped. When the drive begins to run out of reserve sectors S.M.A.R.T. tells you failure is imminent.

The only advantage of a full format is that you thermally cycle the hard drive fully and thus might trigger a potential mechanical failure before your put all your precious data on it.

Cheers

 

[Grall]

Well, to be perfectly fair, we also have to consider that higher capacity drives have been adding more platters to the mix.

Well, not to be a smartass or anything razz, but no, not really. IBM (which later on became Hitachi) has used up to 5 platters at least since the 75GB max drive size generation - the infamous "deathstar" drives that used glass platters. Unfortunately, drive firmware rested the heads for too long over the same cylinders, causing the "pixie dust" surface treatment to overheat, thus causing the drive to develop clicking syndrome, which quickly killed it...

IBM/Hitachi has historically been pretty unique in squeezing in 5 platters in a drive, with most manufacturers choosing to settle on 4 tops. This has let Hitachi launch several capacity-leading drives using lower capacity platters sooner than other manufacturers.

Therefore, a linear relationship between platter density and sustained transfer speed could be entirely feasible

Yeah, theoretically. However from what I understand from reading posts by harddrive gearheads at places like Storagereview.com for example, scaling linear transfer rate is not exactly easy, therefore most of the capacity increase seems to have come from track density scaling rather than sector density scaling.

This bears out from the fact that capacity has increased a lot faster than linear transfer rate. Drives have managed 100ish MBs per second for a couple years now, while capacity has exploded twofold at least.

It looks like most of the 4TB units are using a five platter system, which is pretty crazy...

I actually haven't been checking out platter counts for a long time now as my current 2TB drive is only about half full, and it's gotta be at least 2 years old now. If Seagate and WD are now using 5 platters in their flagship products that would be pretty unique as I don't think they've ever done that before.

 

[Rodéric]

I don't think I've done a slow format in at least 6 years, likely 10.

 

[Grall]

I'd say it's still relevant, and useful, from time to time... For example to prevent old bits of old files and directory structures and whatnot getting mixed up with current stuff in case there's problems with the file system.

Also, when you want to get rid of the drive, to prevent people snooping on your infos...

 

[Blazkowicz]

using shred /dev/sda from a linux live CD would protect you better, in the scenario when a three-letter-agency with millions dollars of special equipment in a clean room try to work out what every 1 and 0 were on the platter.

it's better than physical destruction. saw a poor 80GB smashed hard drive on the street, inside some kind of slim dell optiplex thrown away.
they certainly did take the right decision if they did not know of shred (or something else) but what a sad waste. I got to keep the ddr2 pc4200 sticks and put them in my server.

 

[Grall]

There's no need for any shred, or anything like that. You overwrite data on any relatively modern harddrive and it's GONE. Poof. Can't be recreated again, regardless how many three-letter agencies and however much moeny you throw at the drive.

Just format the drive once, and that's all you ever need.

 

[Davros]

You know there are programs that disagree with you.

 

[Grall]

What programs, and how would a program disagree?

This has been studied you know, and the tolerances in modern drives are so small that there's no (dechiperable) residual charge left for a TLA agency to piece together to recreate previously overwritten data.

Heck, even reading the drive in the first place incorporates guesswork, using PRML tech... Forget getting back any overwritten stuff. It's gone. Dead and buried.

 

[Davros]

Ahh, you've stated 2 differing conditions

You overwrite data on any relatively modern harddrive and it's GONE

Just format the drive once, and that's all you ever need.

I was replying to the second condition

 

[Grall]

I have not stated 2 differing conditions... What kind of dope are you smoking?

 

[Malo]

You two are like bickering children on some threads lol

 

[Davros]

There's no need for any shred, or anything like that. You overwrite data on any relatively modern harddrive and it's GONE. Poof.

Just format the drive once, and that's all you ever need.

Are they not 2 different conditions ?
1st quote says overwrite data
2nd quote says just format, format doesnt overwrite data

Note that reformatting a disk does not erase the data on the disk, only the data on the address tables.

 

[Albuquerque]

Are they not 2 different conditions ?
1st quote says overwrite data
2nd quote says just format, format doesnt overwrite data

Just to be clear, a "quick format" just overwrites the addressing tables. A full format writes zeros to the entire disk. That may be the source of your confusion

 

[Tahir2]

I quick format new drives and when reinstalling Windows for a customer.
If the drive needs checking I use Hitachi DFT - normally very good at finding problems.
If the drive has bad sectors I (or the customer) gets a new drive.

Seems like a good plan of action.. unfortunately some field engineers I have bumped into don't even know what a bad sector is!

 

[Blazkowicz]

There's no need for any shred, or anything like that. You overwrite data on any relatively modern harddrive and it's GONE. Poof. Can't be recreated again, regardless how many three-letter agencies and however much moeny you throw at the drive.

Just format the drive once, and that's all you ever need.

oh that makes sense, I don't know if that story of reading individual charges has always been an urban legend or if it were feasible up until 20GB disks or before GMR drives or something.

if you have to get rid of a ten year-old hard drive containing customer info or whatever, dunno. in truth no one will bother trying anything if it's fully formatted so that's a nerdy debate. and btw I won't really "format" it, just dd if=/dev/zero of=/dev/sda will make it perfectly empty with no MBR and no table of partitions

 

[Davros]

@Alby I know, I'm not confused
from wiki

As in file deletion by the operating system, data on a disk are not fully erased during every high-level format. Instead, the area on the disk containing the data is merely marked as available, and retains the old data until it is overwritten

Reformatting is a high-level formatting performed on a functioning disk drive to free the contents of its medium. Reformatting is unique to each operating system because what actually is done to existing data varies by OS. The most important aspect of the process is that it frees disk space for use by other data. To actually "erase" everything requires overwriting each block of data on the medium; something that is not done by many PC high-level formatting utilities.

 

[Albuquerque]

Ah. Well then, Windows SUCKS

It turns out that, in order for Windows to truly write zeros to the disk, you have to use the command line parameter /p 1 (1 can be anything, but 1 is the minimum). Interesting. Thanks for the correction!

 

[Blazkowicz]

wow, I've found the source for all the tinfoilhattery!

http://en.wikipedia.org/wiki/Gutmann_method#Criticism

also "Secure Erase" has been a standard procedure that has taken care of the problem forever since over a decade.

now, shred can be a great command as it works on single files. but only on older, less complicated file systems.

 

[Grall]

@Alby I know, I'm not confused
from wiki

Wiki doesn't speak the whole truth. A format traditionally does indeed involve overwriting the whole drive (and the quick format variety is a historically fairly young concievement, intended for impatient people, typically of the home user variety), so naturally when I am talking about overwriting the drive, I speak of a full format.

This is self-evident, my friend.

 

[Davros]

I speak of a full format.

No doubt with /p 1 on the end