Scheduling Background Tasks

The 3DM Configuration display allows routine maintenance of storage media by scheduling array rebuilds, initialization, array verifications and media scans. The background tasks selected are only performed during the scheduled time. Depending on the schedule and system workload, background tasks may require more than one

scheduled duration to complete. The day of the week (or daily) time and duration to perform the selected background tasks can be specified using the pull-down menus. When finished, be sure to click on the Save Schedule button to confirm the entries.

 

Background Task Features

Selecting the Rebuild/Initialize feature forces rebuilds and initialization to be performed only during the time specified by the schedule.  If this feature is not selected, rebuilds and initialization can operate anytime they are required. This feature affects only redundant arrays (RAID 1, 5 and 10).

 

The Verify feature verifies redundancy of all RAID 1, 5 and 10 arrays.  

 

The Media Scan feature continuously scans all drives (including hot-spares) for media errors.

 

 

Examples of Background Task Priorities

The following examples assume the scheduled duration is four hours.

 

• Only Verify is selected: The verification operation is performed during the scheduled window. If the operation completes with time remaining in the window, the operation begins again on the same array (if there is only one array) or continues on to additional

redundant arrays. The verify operation stops when the duration in the scheduled window completes.

 

• Only Media Scan is selected: The media scan operation scans each drive starting at the lowest port. If all the drives have been scanned and there is time remaining, the operation begins scanning the lowest port again and continues until the scheduled time completes.

 

• Verify and Media Scan are selected: Both tasks run sequentially within the scheduled window. If the scheduled duration is four hours, the verification operation is run during the first two hours and the media scan operation follows during the remaining two hours. If the duration is only one hour, only the verification operation is performed.

 

• Rebuild/Initialize, Verify, and Media Scan are selected: If all three operations are selected and a rebuild/initialize operation is required, the rebuild/initialize operation is performed first. If this operation completes within the first two hours of the window, a verification operation starts. If the rebuild/initialize operation completes in the last two hours of the window, the media scan operation starts.