The file smart.txt contains the SMART data (Self-Monitoring, Analysis and Reporting Technology) of the ATA controller of the hard disks. This information is available for all hard disks except for the xx20 series 3RU models in which the hard disks are behind a hardware RAID controller.
The following fields are interesting from a possible failure point of view:
Current Pending Sector Count: Number of sectors the hard disk controller thinks are unstable but not yet reallocated.
Offline Uncorrectable: Number of sectors which have been attempted to reallocated but which failed. The data in there is lost.
Raw Read Error Rate: The checksum of the data read from the platter was incorrect and error correction was required to restore the data.
Seek Error Rate: The number of seek related issues, when the arm of the servo does not properly position the head on the right track.
Reallocated Sector Count: The number of sectors which have been reallocated to a different sector on the disk.
Reallocated Event Count: Number of times a sector has to be reallocated to a different location on the drive.