RAID configuration
This window determines how RAID works on the filer. To reload the current settings from the filer, click the Reload Settings button. To view the changes that you made, click the View Changes button. After you make a change, click the Save Changes button to save the changes to the filer.

The following list describes the fields in this window:

RAID Timeout
Sets the time, in hours, that the filer runs in degraded mode before an automatic shutdown. A filer is in degraded mode if either of these conditions is true:
  • one disk in any volume has failed
  • the batteries on the NVRAM card are low

Cluster considerations

The RAID timeout value must be the same on both filers in a cluster, otherwise takeover might not occur properly.

RAID Reconstruct Speed
Specifies the speed of RAID reconstruction. The speed ranges from 1 (slowest) to 10 (fastest). The filer uses the number 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.
 

Cluster considerations

The RAID reconstruct speed must be the same on both filers in a cluster, otherwise takeover might not occur properly.

 
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 reduces the possibility of a failure of two disks within the same RAID group. RAID cannot recover from a disk media error if there is already a failed disk in the same RAID group.
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 might be an unrecoverable error on a disk that you cannot fix before the next scrub.