Low Level vs High Level Format

[KlumpDud]

What's the difference?

[juppy]

Hi KlumpDud

Most of what you hear about formatting anymore is referring to high level formatting. High level formatting basically creates and configures the file allocation table (FATs) and creates the root directory. This is what you are doing when you use the FDISK program to set up a hard drive. Low level formatting creates the sectors so they can accept data, sets the interleave, and makes the boot sector. Low level was done on pre-IDE drives. All the newer IDE/EIDE drives are low level formatted at the factory. That's why you really don't hear low level and high level discussed much anymore because there's really only one that you do anymore, the high level. hth :)

[Tuf]

Plus it's pretty easy to destroy a modern drive doing a true low level format.

[dldz]

Hi Klump Dud, heres a good link for some reading on the different types and what the major differences are Check it out here (http://www.pcguide.com/ref/hdd/geom/format-i.htm)
Don

[KlumpDud]

I see...
how exactly do you do a high level format? (check my profile for system specs)

[dldz]

You might want to put your specs there (in your profile)

[Confused]

Some people refer to a zero fill as a low level format. I don't know if that is accurate, but I just used a zero fill to recapture full capacity of a drive that had contained Linux.
Chas

[glc]

The "format" function of an operating system is a high level.

[morriswindgate]

Go Here it is all explained
http://www.pcguide.com/ref/hdd/geom/formatUtilities-c.html

And Tuf you cannot do a true LLF on a modern drive, but many people call Zero Filling an LLF which will not hurt the drive physically.

[Tuf]

Sure you can, but like I said you'll probably ruin the drive.

[KlumpDud]

Then how do you erase all record of anything on the drive. For example, if you are selling or giving away your hard drive and all you do is a high level format, the information on that drive can still be retreived by someone who knows how. How do you permanently get rid of it?

I read in a recent issue of PC World that LLF is a way to completely erase your drive if you need to.

[Blakhart]

A true low level format will take many hours, often 5 to 9 or more, depending. You had better have a stable system and a ups to ensure you do not ruin the drive.
I do low levels all the time and have yet to ruin one. Have seen many drives that had "bad" sectors recovered by low level runs.
They are great when you need em, otherwise shave off 6 hours and do a format or zero fill. The WD ute I use to zero fill has a quick fill and a full fill. The quick just erases the first and last million sectors, taking about 15 secs. The full erases every sector, and takes 16 mins.

[TwoRails]

Hi Blakhart and All,

I use to do it all the time, but not for years.... is the address still something like C000?? Just curious...

TwoRails

[KlumpDud]

So you can do it. How? And why do I need a UPS? The odds of a power outtage are slim.

[Blakhart]

Yeah you can, just get the drive maker's ute and floppy away. If you are willing to take the risk, go ahead and LL without a ups.
I did it at home the other day on a older 47gig scsi drive, the scsi card offered to LL it for me so I said yes before I thought about it. With my scsi2uw card and drive, I foresaw about 24hrs or more of LL going on in my head. Quite a relief when it took about 4. Dual cpu's may have helped, dunno. This was not using a ups, but I took the risk knowing.

[morriswindgate]

Just use a Zero Fill Utilitity and then re-partition and format the drive.

[glc]

It bears repeating that a true low level format WILL destroy an IDE drive, but it's safe on SCSI and MFM, and I believe ESDI. If you want to wipe an IDE drive, you use a zero fill, if you want to remove evidence even better you use some kind of secure wipe multiple times.

[TwoRails]

Originally posted by glc
It bears repeating that a true low level format WILL destroy an IDE drive, but it's safe on SCSI and MFM, and I believe ESDI. If you want to wipe an IDE drive, you use a zero fill, if you want to remove evidence even better you use some kind of secure wipe multiple times. Here's a cut-n-paste from Maxtor's site:You cannot perform a true "factory" low-level format on your Maxtor and Quantum® ATA hard drive. The servo, sector layout, and defect management information contained in the low-level format is designed to last the life of the drive. This information and the way it is written cannot be duplicated in any way outside of the factory.

However, you can use utilities such as PowerMax (version 3.3 or newer) or MaxBlast 3 to purge the drive of a corrupted master boot record, a boot block virus, or to clear the drive of any recoverable bad sectors or bad clusters.

To perform a non-factory low-level format using PowerMax please select the Write Disk Pack option.

To perform a non-factory low-level format using MaxBlast 3 please select the Zero-Fill Drive option located under "Utilities".

Note: High capacity drives take longer to complete. Allow sufficient time to complete the test. Several hours to overnight may be needed. A full Low Level Format remains the most effective test for a drive with intermittent problems.

HTH

TwoRails

[glc]

Correct - the "non factory low level format" is a zero fill.

[KlumpDud]

Cool, so how do I clear drive of any recoverable info?

[Steve1]

"Cool, so how do I clear drive of any recoverable info?"

You can download ERASER (http://www.heidi.ie/eraser/) then use the "Boot and Nuke" function to create a floppy that will get rid of all data.

The only problem I've had with it is that it takes quite a while. 5-10 hrs. depending on the size of the drive.