SSD Drive Diagnostics
SSD drive diagnostics is a complicated area requiring professional tools, knowledge, and experience.
Advantages of Solid-State Drives over Hard Disk Drives
Unlike the traditional hard disk drives that store data by using the magnetism, solid-state drives (SSDs) neither use this technology, nor do they have any mechanical movement. With no moving parts inside, SSDs are faster than HDDs. A tiny fraction of millisecond is needed to access data stored on the SSD. Because they weigh less and require a little space in comparison with traditional hard drives, SSDs (especially Multi-Level Cell SSDs) already gained mass popularity among the end-users and computer manufacturers. They are silent doers! The absence of mechanical movement means a steady performance and endurance to vibrations and sudden shock occurrences. From a data recovery standpoint, SSD data recovery operations do not need a cleanroom environment.
Different solid-state drives have different lifespans. It mostly depends on the manufacturer. And the manufacturer is still improving the performance of SSDs. It is important to note that SSDs have a limited-service time, and their approximate lifespan varies between 5 (Multi-Level Cell) and 10 (Single Level Cell) years. This lifespan is calculated based on the capacity of write-erase cycles per cell.
Data recovery from Solid State Drives
So how SSD store data? They store data in multiple memory chips, and a controller manages these chips. Flash SSD technology uses pages and blocks instead of sectors, as we used to address in HDDs. NAND flash-based SSDs read and write data in units known as pages, and in a typical SSD, 128 pages constitute a single data block. Data recovery from SSDs requires a different set of skills and experience. If an SSD suffers physical damages, advanced manipulations are needed to execute data recovery operations. With logical issues, however, different aspects should be taken into account before any data recovery activities.
How challenging is it?
The multiple memory chips inside an SSD drive store data dynamically, just like RAID structures do. Depending on the NAND-Flash technology (SLC, MLC, eMLC), the endurance of SSDs is different. Over the years, cells that stores a tiny fraction of data eventually wear out. The more “dead” cells, the more challenging a full data recovery becomes. MLC/eMLC type based SSDs are certainly not advisable for a server environment. Especially when data processing capacity per day is in hundreds of gigabytes. For example, in a database server, it is recommended to use a combined SSD+HDD/SAS format. While the system and the actual software located in an SSD to gain maximum speed, the working data will be safer in a traditional hard drive.
Because of their RAID-like structure, even with completely healthy memory chips, data recovery from SSDs is different in comparison with another type of NAND-based media.
Types of SSD failures and damages
With SSDs, considering all the above-mentioned factors, data loss can occur due to several reasons. It includes natural wear, as well. Here is the list of generalized failures:
- Software/firmware corruption
- Virus Attack
- Mapping table corruption
- Deleted data by using TRIM command
- Memory chip damages
- Controller chip failures
- Power surge failures
- Component damages
- Fire damage
- Natural cell wear and degradation
- Circuit board damages
If you notice that the file copying/reading speed on your SSD has drastically decreased, take it as a possible early symptom of failure. There are free tools available on the Internet to check the health of your SSD.