Always certify a disk before using it

Disk drives only receive limited testing when they are manufactured, not a comprehensive testing of the entire disk surface. Manufacturers expect that users will discover faulty drives as they use them. Drives are tested to ensure that they can start and stop reliably and that they can read and write to a small sample of sectors. You should not trust your valuable work on these disks until you know that all of the sectors on them can reliably store data. Otherwise, you might write out an important file to a volume on the disk only to discover later than you can’t read it back (on a large drive, it may take a year or more to reach the part of the drive that is defective).

You can test all of the sectors on your new disk by using SoftRAID’s disk certify function. We highly recommend a three-pass certify for all new drives you intend to put into service storing your valuable data.

Important: A disk certify will erase all data on a drive permanently.

The Certify process will write random data to every sector on the disk, and then read it back to ensure that the drive can write and read data across the entire surface reliably. On a three-pass certify, the first two passes are random data. The last pass is zeros so the drive ends up in “as new” status. After successfully completing a three pass certify on your new disk using SoftRAID, you can be confident that your drive can store your files and read them back correctly.

Note: Rotating hard disk drive certification is thorough but time-consuming. A three-pass certify on a 4TB drive can take 48 hours depending on how it is connected and longer for 2.5” drives. A rule of thumb is one day per 2TB capacity.

Should I certify SSDs or NVMe/flash media?

Yes, we strongly recommend a three-pass certify for all flash media. While solid-state drives don’t have mechanical parts, they can still have unreliable regions that may cause data loss. Additionally, certification “refreshes” SSDs, restoring write performance to optimal condition.

Flash media requires a minimum of two-passes to be effective, though three-passes is recommended for maximum confidence. A 2TB SSD typically takes 4-8 hours to complete a three-pass certify, depending on the interface speed.

Important: Do not certify SSDs with less than 10% remaining life, as the intensive write operations may accelerate failure.