The two types of data recovery are logical and physical. Logical data recovery is when you need to recover data that is corrupt, erased, or damaged in some way that makes the computer not able to read the data as usual. In a logical recovery, the actual hard drive holding the data is working perfectly fine. Physical recovery is when there is a problem with the hard drive itself and that hard drive problem is why the data needs to be recovered.
Logical Data Recovery
The most common forms of logical recovery are accidentally erased files or accidentally formatting a drive. Other frequent causes include the computer losing power during tasks that cause important data to become corrupt, or a program or operating system issue that causes corruption in files.
Logical data recovery is usually completed by running data recovery software. There a hundreds of programs for completing logical data recovery, but some of the best are UFS Explorer, Data Rescue, R-Studio, and the Get Data Back suite of tools. There are also recovery companies that have custom tools for recovering certain types of files that are not common.
Best practices for logical data recovery
There are a few things that are best practices when working with logical data recovery. You want to make sure to follow these rules to be able to complete a logical data recovery as safe as possible.
- Always work with an image of the original drive. This means your first step in a logical recovery is to clone the original drive onto a different drive. You want to do a full clone so the deep scan you run on this clone will pickup all data from the original drive.
- Always recover any data onto a different drive. So you will have your original drive that you cloned set aside and not touched again during the recovery, the clone of that drive that you are running your recovery software on, and a third blank drive that you are moving any recovered data onto. The reason you always move data onto the third drive is that you don’t want to cover up any deleted or missing files by moving recovered data onto the drive you are recovering from.
- Run deep scans instead of quick scans in almost all software. Running a quick scan to see if the folder structure will easily come back is fine, but don’t use that scan for recovering the data. Switch to a deep scan and recover after that deep scan is complete. It will take longer for the recovery to complete, but the results will be the best possible.
- Use good recovery programs. Some are expensive, but as a recovery lab you need to invest in the best recovery software. Even if your focus is physical recoveries, there are many physical recoveries that end with an intense logical recovery.
Physical Data Recovery
Physical data recovery is the most common form of recovery we see at a data recovery shop. A lot of the logical recoveries get taken care of at computer repair shops, so not as many make it through to us. Some of the most common physical recoveries we see are failing sectors, firmware issues, bad heads after a drop, PCB power issues, and bad preamps.
The idea with a physical recovery is that the data cannot be accessed because of an issue with the hard drive. Once that issue is resolved or at least temporarily fixed, the data is then accessible for transfer to a new drive.
Best practices for physical data recovery
There are a lot of best practices to mention for the different types of physical data recovery, here I will cover some of the more common and important ones.
- Always use a cleanroom environment when you open the cover of a drive. While recovery may be successful without a cleanroom environment, it is not worth the risk of losing the data forever.
- Keep track of all original parts. Sometimes original parts have aspects that will need to be accessed for a successful recovery. I have received drives in the past that were brought to a recovery company before me and I had to ask for the original parts to be able to successfully recover the data (think the printed circuit board, etc.).
- Always image a drive even after you have it working again. A lot of recovery techs want to be done with a recovery and just move the data off the drive onto a new drive to skip the imaging part. Don’t do this. Complete all the steps every time including using a disk imager like the deep spar disk imager to image the failed drive. Start by targeting files that are important, then move onto imaging the entire drive. It may take more time, but it is the safest way to recover data.
- Invest in high end equipment. A PC-3000 is a must (along with years of experience), to ensure you can safely recover data from all the drives you get for data recovery. If you are new to the business, find a shop to work at where you will be monitored and taught by an expert until you have the experience and expertise needed to go out on your own.
When both logical and physical are needed
A lot of physical data recovery projects end with a logical recovery. When a hard drive begins to fail, there will often be issues with the data on the drive. If you keep using a drive that is having issues, corruption might be present that will cause issues even after all the sectors are recovered. Be prepared to deal with both physical and logical issues if you are offering physical data recovery.
Do you need help with a logical or physical data recovery?
I offer logical and physical data recovery services. After over a decade working in the data recovery industry, I have the experience and expertise needed to recover your data safely.