The hardware self tests built in IDE / Serial ATA / SCSI / SAS hard disks are the perfect solution to test the hard disk status quickly or with very high detail. Usually the short and extended self tests are supported by the hard disks but some models support other (conveyance) self test also. The list of all supported self tests and the estimated time of such tests are displayed on the Information page of the hard disk.
The self tests are non-destructive, they do not affect the data stored on the hard disk. During the test, the hard disk is still usable but may be slower (and vice versa: hard disk usage may make the test much longer. It may be important for a system hard disk where the op. system or other software may cause much read/write operations).
The Short self test verifies the major components of the hard disk (read/write heads, servo, electronics, internal memory, etc). This test takes only some minutes.
The Extended self test performs the above and it has a complete surface scan which reveals the problematic areas (if any) and forces the bad sector reallocation. It is recommended to periodically use this test to verify the disk health - especially on a hard disk with less than 100% health.
The Conveyance self test (if supported) performs manufacturer-specific test steps. This usually verifies the mechanical parts of the hard disk to ensure that no handling damage occured.
The date and results (successful completion or the failing hard disk element) of the last self tests are displayed on the Information page. On this page, all supported hard disk tests can be started manually - or it is possible to configure automatic (scheduled) hard disk tests on the Operations page (Professional version only).