Recovering from a disk failure with a hot spare disk

About this section

How disk failures affect the NetCache appliance depends on whether a hot spare disk is installed. This section describes how the NetCache appliance reacts to a disk failure when a hot spare disk is available.

What happens if a hot spare disk is available

If a hot spare disk is available when a disk failure is detected, the hot spare disk automatically comes online as a replacement. The missing data is rebuilt on the hot spare disk in the background so that the interruption to file service is minimized.

The Messages log file records information about the disk failure and hot spare disk replacement activity. The Messages log also logs any failures detected in the periodic checks of the hot spare disk.

Automatic shutdown does not occur if a single disk drive fails and a hot spare disk is available. After the appliance is finished rebuilding data on the hot spare disk, replace the failed disk with a new hot spare disk as soon as possible to ensure that a hot spare disk is always available in the system.

If you do not replace the hot spare disk and another disk fails, a warning message is displayed every hour to remind you to replace the disk. The appliance gracefully shuts down every 120 hours until a replacement disk is installed.

Viewing the hot spare disk in the GUI

You can view the hot spare disks available on your NetCache appliance on the Disk - Management page (Maintenance tab > Disk > Management). The disks are labeled spare in the Disk Type column.