Learn how to erase only the used space on a storage drive without affecting the existing partitions or data. This article explains the problem and the solution in simple steps.
If you want to securely wipe the data from a storage drive, you might think that formatting it or deleting the partitions would do the trick. However, these methods only remove the references to the data, not the data itself. The data can still be recovered by using special software or hardware tools. To prevent this, you need to overwrite the data with zeros or random patterns, which makes it impossible to recover. This process is called erasing or sanitizing the drive.
However, erasing the entire drive can take a long time, especially if the drive is large or has multiple partitions. Moreover, you might not want to erase the whole drive, but only the unused space, leaving the existing partitions and data intact. This can be useful if you want to sell or donate the drive, but keep some personal or sensitive information on it. Or, you might want to erase the free space on your system drive to improve its performance and security.
In this article, we will show you how to erase only the used space on a storage drive without affecting the existing partitions or data. We will use a free and open-source tool called DBAN (Darik’s Boot and Nuke), which can run from a bootable CD, DVD, or USB drive. DBAN can erase any type of storage drive, including hard disk drives (HDDs), solid state drives (SSDs), and flash drives. It can also erase multiple drives at once, and it supports various erasing methods and options.
Table of Contents
How to Erase Only the Used Space on a Storage Drive with DBAN
Before you start, make sure you have backed up any important data on the drive you want to erase, as the process is irreversible. Also, make sure you have a blank CD, DVD, or USB drive that you can use to create a bootable DBAN media. You will need another computer to download and burn the DBAN ISO file.
- Go to the official DBAN website and download the latest version of the DBAN ISO file.
- Use a free and reliable tool like Rufus to burn the DBAN ISO file to a CD, DVD, or USB drive. Follow the instructions on the Rufus website to create a bootable DBAN media.
- Label the DBAN media and keep it in a safe place.
- Insert the DBAN media into the computer that has the drive you want to erase.
- Restart the computer and press the appropriate key to enter the boot menu. The key may vary depending on your computer model and BIOS settings, but it is usually F12, F10, F9, F8, F2, or Esc. You may also need to disable the Secure Boot option in the BIOS settings to boot from the DBAN media.
- Select the DBAN media from the boot menu and press Enter. You should see the DBAN welcome screen.
- Press Enter to start DBAN in interactive mode. You should see a list of the detected drives and their details, such as model, size, and serial number.
- Use the arrow keys to highlight the drive you want to erase, and press the spacebar to select it. A black box with a white “Wipe” label should appear next to the selected drive. You can select multiple drives if you want to erase them simultaneously.
- Press F10 to continue. You should see the DBAN options screen.
- Use the arrow keys to navigate the DBAN options screen. You can change the following settings:
- PRNG: This is the pseudo-random number generator that DBAN uses to create the random patterns for erasing the drive. You can choose between Mersenne Twister (MT), ISAAC, or /dev/urandom. The default is MT, which is fast and secure enough for most purposes.
- Rounds: This is the number of times that DBAN will overwrite the drive with the chosen erasing method. The default is 1, which is sufficient for most cases. Increasing the rounds will increase the security, but also the time and wear of the drive.
- Verify: This is the option to check if the drive has been erased correctly. You can choose between Last Pass (verify only the last round), All Passes (verify every round), or Off (no verification). The default is Last Pass, which is recommended for most situations. Verifying the drive will increase the reliability, but also the time and resources of the process.
- Method: This is the erasing method that DBAN will use to overwrite the drive. You can choose between Quick Erase (write zeros), RCMP TSSIT OPS-II (write four random patterns), DoD Short (write three patterns: zero, one, and random), DoD 5220.22-M (write seven patterns: zero, one, random, and their complements), Gutmann Wipe (write 35 patterns based on various magnetic encoding schemes), or PRNG Stream (write a continuous stream of random patterns). The default is DoD Short, which is compliant with the US Department of Defense standard and offers a good balance between speed and security. Choosing a different method will affect the time and effectiveness of the erasing process.
- After you have chosen the desired settings, press F10 to start the erasing process. You should see a progress screen with the estimated time and speed of the operation.
- Wait for the erasing process to complete. Depending on the size and type of the drive, the chosen method and options, and the performance of the computer, the process may take from a few minutes to several hours. Do not interrupt the process or turn off the computer, as this may damage the drive or leave some data recoverable.
- When the erasing process is finished, you should see a message that says “DBAN succeeded. All selected disks have been wiped.” You should also see a log file with the details of the operation, such as the drive model, serial number, method, rounds, errors, and status.
- Press any key to reboot the computer. Remove the DBAN media and store it in a safe place. You can reuse it for future erasing tasks.
Frequently Asked Questions (FAQs)
Question: Is DBAN safe to use?
Answer: DBAN is a safe and reliable tool that has been used by millions of users and organizations to securely erase their storage drives. However, as with any software that modifies the data on your drive, there is always a risk of data loss, corruption, or damage. Therefore, you should always backup any important data before using DBAN, and follow the instructions carefully. You should also use DBAN only on drives that you own or have permission to erase, and be aware of the legal and ethical implications of erasing data.
Question: Can DBAN erase SSDs?
Answer: DBAN can erase SSDs, but it is not recommended. SSDs use a different technology than HDDs, and they have a limited number of write cycles. Erasing an SSD with DBAN may reduce its lifespan, performance, and reliability. Moreover, DBAN may not be able to erase all the data on an SSD, due to the way SSDs manage and store data. A better way to erase an SSD is to use its built-in secure erase feature, which can be accessed through the manufacturer’s software or the BIOS settings. Alternatively, you can use a specialized tool that supports the TRIM command, which tells the SSD to erase the unused blocks of data.
Question: Can DBAN erase encrypted drives?
Answer: DBAN can erase encrypted drives, but it may not be necessary. Encrypted drives use a special key to encrypt and decrypt the data on the drive. Without the key, the data is unreadable and inaccessible. Therefore, if you lose or forget the key, or if you delete the encryption software, the data on the drive is effectively erased. However, if you want to be extra sure, you can use DBAN to overwrite the encrypted data with random patterns, making it even harder to recover.
Question: Can DBAN erase external drives?
Answer: DBAN can erase external drives, such as USB flash drives, SD cards, or external hard drives. However, you need to make sure that the external drive is detected and recognized by DBAN, and that you select the correct drive to erase. To avoid confusion, you can disconnect any other drives that you don’t want to erase, and label the external drive clearly. You can also use the serial number or the size of the drive to identify it in the DBAN interface.
Summary
In this article, we have shown you how to erase only the used space on a storage drive without affecting the existing partitions or data. We have used a free and open-source tool called DBAN, which can run from a bootable CD, DVD, or USB drive. We have explained the steps to download and burn the DBAN ISO file, boot from the DBAN media, select the drive to erase, choose the erasing method and options, and wait for the erasing process to complete. We have also answered some frequently asked questions about DBAN and its features.
We hope you have found this article helpful and informative. If you have any questions or feedback, please feel free to leave a comment below. Thank you for reading!