This window determines how RAID works on the filer. After you make a change, click the Save Changes button to save the changes to the filer. To view the changes that you made, click the View Changes button. To reload the current settings from the filer, click the Reload button.
The configurable fields in this window are:
Sets the time in hours the filer runs in degraded mode before an automatic shutdown.
A filer is in degraded mode if either of these conditions is true:
Specifies the speed of RAID reconstruction. The speed ranges from 1 (slowest) to 10 (fastest). The filer uses the number that you specify to determine the percentage of CPU time used for RAID reconstruction. Because RAID reconstruction consumes CPU time, sometimes increasing the speed of reconstruction slows down the filer's network operations. The default speed is 4, which means approximately 40% of the CPU time is used for RAID reconstruction.
RAID scrubbing is a procedure the filer uses to increase data availability. The filer scans each disk in the RAID group for media errors. If media errors are found, the filer tries to fix them by reconstructing the data from parity and rewriting the data. RAID scrubbing protects the system from a failure of two disks, because without scrubbing, RAID would not be able to recover from a disk media error while the system was running in degraded mode.
The scrubbing process runs only while the filer is in normal mode. That is, the filer scans the disks only when all disks are operational. Although scrubbing slows the filer, network clients do not notice the change in the filer's performance because scrubbing starts automatically at 1:00 a.m. on Sunday when most filers are lightly loaded.
Disable scrubbing if you have a recurring problem that scrubbing encounters. For example, there may be an unrecoverable error on a disk that you cannot fix before the next scrub.