RAID Configuration
- RAID Timeout
-
- RAID Reconstruction Speed
-
- RAID Scrub Enabled
-
RAID Timeout
Sets the time in hours the system runs in degraded mode before an automatic shutdown.
A filer is in degraded mode if:
- one disk in the file system has failed, or
- the batteries on the NVRAM card are low (if the filer is a NetApp F200, F300, F500, or F600 series filer).
RAID Reconstruction Speed
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 Scrub Enabled
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 somewhat, network clients may not notice the change in the filer's performance because scrubbing starts automatically at 1:00 a.m. on Sunday when most systems are lightly loaded.
By default, RAID scrubbing is enabled. You may want to 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.
NetApp Filer Configuration Help - 28 AUG 1997