Hard Drive and Cleanroom Technology - behind the scenes

Thursday, December 31, 2009 by The Data Experts

Hard drive technology has been around since the Fifties. The large multi-platter based systems, IBM 305 RAMAC, were only used in large mainframe systems. It wasn’t until the Seventies and Eighties that hard drive storage became more available. This was due to cost reductions, innovation from magnetic media formulations, storage capacity, performance, and manufacturing techniques.

Hard drive storage manufacturers have always been working to improve the technology. Storage space, data transfer rates, and internal error checking have been the guiding principles of hard drive technology. Ontrack works hard to maintain our capabilities to be compatible with these emerging technologies so that we can provide the best hard drive recovery for your client’s data. What are some of the advancements in hard disk storage devices? What are some common data loss scenarios with hard disk storage? What are some of Ontrack's capabilities that set it apart from other data recovery companies? This document will help answer these questions and more. Let’s begin with looking at the inner workings of the hard drive itself.

Hard Drives — Technology in Action

As you know, hard drives are a combination of sophisticated electronic and mechanical systems that incorporate a number of specialized motors and electro-mechanical components to read and write data.

Hard drive technology has substantially advanced in the past 10 years. In fact, hard drives are designed to manage themselves in addition to reading and writing data. Hard drives today use a number of algorithms to verify data on the drive and also maintains a ‘Defect Management’ list internally that constantly monitors their own health and performance . If a sector is beginning to fail, the hard drive’s electronics will remove that sector from use. In addition to this, S.M.A.R.T. (Self-Monitoring, Analysis and Reporting Technology) circuitry has been incorporated on many hard drives and is used to monitor all of the internal systems.

Despite these safeguards, hard drives can fail. There can be a number of reasons for hard drive failure, for instance physical damage can result when the hard drive or case is jarred while operating or even when powered off. Power spikes or fluctuations can damage the electronics or corrupt the data on the drive. Internal mechanical parts can seize up due to high temperatures if the drive does not have enough airflow to keep the unit cool.

Types of common failures include:

ProblemDescription
Internal Mechanical FailureThis is the failure of any moving mechanical component found within a storage device.
Intermittent FailureThis is the failure of a storage device to operate reliably. In some cases it may not be possible to isolate the exact fault.
Physical Media DamageThis can occur when a head has physical contact with the surface of platter. When the head(s) come into contact with the platter it digs into the platter removing a chunk of the media. As the platter spins, debris is scattered causing read errors.
Media CorruptionThis type of damage can effect the magnetic information stored on the media. It can affect both the user data stored on the drive and the critical drive servo information that controls the positioning of the heads.
Electronics FailureThis is the failure of a storage device’s circuitry (the brain of the storage device).

Hard Drive Recovery — Exposing the Myths

A common misconception about hard drive data recovery is that repairing hard drives means replacing parts. If only it were that easy! Hard drive technology is always changing— manufacturers are constantly using different mechanical designs.

Today’s hard drives have no room for errors when it comes to platter and head alignment. The tolerances are so exacting that hard drive manufacturers even design ways to keep the Base-Casting Assembly, where all the components are attached to, from shifting due to high temperature situations. For instance, one hard drive manufacturer of high performance SCSI based drives actually designs their Base-Casting Assembly with pre-stress points. The assembly does not line up from corner to diagonal corner—it’s pre-torqued. When the casting assembly heats up, the unit actually twists back (thermal expansion) into a true line-up from corner to corner. With the byte-density of most large hard drives today being 4gb to 6gb per square inch, absolute precision is required for these high capacity and high speed drives to operate reliably. Hard drive manufacturers are working to increase how many bytes can be squeezed into a square inch.

The mechanical precision of today’s hard drives makes head assembly replacement nearly impossible without specialized tools. Platter removal is dangerous and will affect how the drive reads the sectors. As previously mentioned if just one component is out of alignment, the drive will not find the required sectors. If the hard disk electronics cannot find the sectors requested by the controller, it may endlessly try to find those sectors or it will shut down the unit.

Mechanical precision is just one side of hard drive technology - the electronics are just as finite. Exchanging circuit boards between drives used to be a quick way to work around a failed circuit board in the past. The electronics are much more complicated, and as a result the different revisions of a circuit board are rarely compatible. The innovations of the past 15 years have made a circuit board swap as a solution a thing of the past.

Today’s hard drives are designed from basic primary components as the foundation first and then other components are built around that. For instance, research and development improvements in platter and magnetic media require research and development improvements in head design. These designs require that the electronics be ‘custom-made’ for that drive. Hard drives are ‘fine-tuned’ to the properties of the storage media and read/write heads. Similar to how a radio is tuned to a specific radio frequency; hard drives are finely tuned to complement data signals that are read from the storage media.

Hard drive manufacturers make large batches of drives so there will be similarities between drive models. However, the Revision Code (proprietary hard drive read-only software that is used by the electronics to manage and operate the hard drive) changes frequently within the same model and batch. Hard drive innovation requires drives to be constantly improved upon. All of this requires extensive training in electronics and computer science to be able to work with these storage devices.

What does it take to recover a hard drive?

To be able to work on hard drives, Ontrack cleanroom engineers have engineering or electronic degrees. Ontrack has a dedicated research and development department that is made up of clean room engineers from our domestic and international offices. They work together with the hard drive manufacturers to find the best scientific approaches to hard drive failures.

The technological innovations in the hard disk storage industry have inspired Ontrack Data Recovery clean room engineers. They closely follow advancements made within the industry. Ontrack designs its own software, hardware, and electronic tools to work with hard disk storage devices. Storage hardware should not be considered unrecoverable until determined so by Ontrack's engineering staff. Ontrack has performed successful recoveries on drives that have been in fires, floods or that have had damage to the Base-Casting Assembly. In some cases where there is physical media damage, Ontrack engineers can force the drive to read around those bad areas using specially designed electronic modules and software that work directly on the hard drive.

What does this mean for you?

You are well positioned to be a recovery solutions provider for your clients by working with Ontrack Data Recovery. Advancements from Ontrack cleanroom engineers worldwide result in quality recoveries. This attention to advancing technology has saved severe losses in time, money and digital resources for thousands of companies. While most companies have a backup program in place, data recovery produces the latest original files - not an older copy of the file.

Ontrack works with hard drive manufacturers in producing software for hard disk installation. Ontrack Data Recovery also writes hard drive analysis software for manufacturers. Many manufacturers and OEMs recognize Ontrack's leadership in this field. Ontrack's experience with hard drives goes back to our roots - the founders of Ontrack came from the storage division of Control Data Institute.

By partnering with Ontrack, you have extended your capabilities in disaster recovery. While a disaster is a traumatic and frustrating experience, having a hero during rough times is reassuring. By utilizing Ontrack recovery capabilities you can be that hero. We will work with you to get your client’s data back as soon as possible. Our clean room staff will not stop until they get every last bit of recoverable data. Our data recovery lab engineers will do all they can to put the file system back in order so that the original data is found. If there should be corruption in some of the files, we will work on the files with Ontrack’s  EasyRecovery FileRepair software to get all of the usable data back.

All of this provides you with the edge when a disaster happens. Being an Ontrack Partner means you have Ontrack's worldwide resources working for you.