Recovering From Disk Failures; Single Disk Failure; Two Disk Failure; Detecting And Monitoring Disk Failures - Dell DX6000 User Manual

Recovering From Disk Failures

NOTE:
The DX Cluster Services Node system's internal disk storage is
preconfigured as RAID 5.

Single Disk Failure

RAID 5 provides uninterrupted operation of the system if a single disk fails. If
a single disk failure occurs, replace the failed hard drive. For more
information, see Dell DX6a00 systems Hardware Owner's Manual at
support.dell.com/manuals. After the hard drive is replaced, it is automatically
assigned by the RAID controller and rebuilt into the disk group. After the disk
group is rebuilt, the RAID 5 disk group continues to operate normally.
CAUTION:
If a second drive fails before the disk group rebuild is complete, data
loss occurs.

Two Disk Failure

If the system experiences a two disk failure, the RAID 5 group must be
reconfigured and the operating system must be reinstalled. Follow the steps
for recovering from operating system failure listed in Table 5-1.

Detecting and Monitoring Disk Failures

To optimize the protection of the RAID group on the system, it is essential
that you detect hard drive failures immediately. Replacing failed disks
immediately reduces the risk of unplanned downtime and loss of critical data.
Ensure that you replace the failed disk with a new disk of the same or greater
capacity. If drives of greater capacity are used, some usable disk space is lost in
the RAID 5 configuration.
You can use the following methods to monitor the health of the disks:
• Hard drive LED indicators—Monitors the drive activity and reports
failures. For more information, see the Dell DX6a00 Hardware Owner's
Manual at support.dell.com/manuals.
• Dell OpenManage Server Administrator—Monitors the health of the
internal disks.
Disaster Recovery
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