3Ware 9550SXU-12 User Guide - Page 242

3DM 2 Reference Self-test Schedules Unlike scheduling of rebuilds and verifies, scheduling of self-tests is always followed. To disable self-tests you either remove all schedule times, or uncheck the tests listed in the Tasks column. Note: Only the checked tasks will be run during the scheduled times. If none of the tasks are checked, self-tests will never run, even if you have scheduled time slots set. Two self-tests can be scheduled: Upgrade UDMA mode. (Only applicable to PATA drives.) This test checks the speed at which data transfer to drives is occurring, to see if the UDMA mode can be increased. (If you are already running at the fastest UDMA mode, then this self-test has no effect.) The UDMA mode can become downgraded in the event that cable CRC errors are encountered, requiring multiple retries to read sectors. In severe cases, the UDMA mode may be downgraded from ATA 150 to ATA 133, to ATA 100, to 66, to 33. This check is also done every time the system is booted. Check SMART Thresholds. This test checks to see whether SMART thresholds have been exceeded. The SMART thresholds indicate when a drive is likely to fail, based on the number of errors that have been recorded through SMART (Self-Monitoring, Analysis and Reporting Technology). If any of the disk drives have detected a "threshold exceeded" condition, then an AEN is logged to the 3DM Alarms page. Moreover, if anything unusual is found during any self-test, it will be logged as an Alarm. 230 3ware SAS/SATA RAID Software User Guide, Version 9.5.1