CRITICAL WARNING: Never re-assign a drive exhibiting a "History of Failure," SMART error, or persistent I/O timeout as a RAID hot spare. Rebuilding an array onto a degraded member drive significantly increases the risk of a secondary disk failure during rebuild, which can destroy the entire RAID array.
It's not unusual to get a “History Of Failure” warning sign in your Dell EqualLogic PS Series storage array. Dell EqualLogic storage arrays are a great option for small businesses because they're affordable and easy to use. But like all storage arrays, they're not immune to problems. The History of Failure message appears when a disk failed before.
But if you see this message too often, it's time to replace the disk. Dell EqualLogic doesn't support hot-swapping, so you'll have to schedule some downtime.
You may check your disks on the health status of your disks:
- Up status: Online, Spare
- Warning status: Alt-Sig, History Of Failures, Replacement
- Down status: Encrypted, Failed, Not Approved, Offline, Preempt Failed, Too Small, Unhealthy, Unsupported Version
How to avoid data loss when the disk presents a History Of Failure error
To avoid data loss from a History of Failure warning, you must monitor the disks on your array, checking for any issues, and update your Dell EqualLogic firmware regularly. New versions often include fixes for known issues, including those that can cause data loss.
Updating your Dell EqualLogic RAID firmware
Step 1. Download the latest Dell EqualLogic RAID firmware from the Dell support website. If you don’t have an account yet, you’ll need to create one to access the firmware update kit.
Step 2. Decompress the file and run it.
Step 3. Follow the instructions in the wizard to update your Dell EqualLogic RAID firmware.
Why you must never re-assign a degraded drive as a hot spare
A common but dangerous practice is clearing the drive's error flag and re-designating it as a hot spare or re-integrating it into the volume. This approach frequently leads to total array failure.
When a RAID rebuild is initiated, the controller subjects all remaining drives and the target replacement drive to continuous, high-volume read/write operations for hours or even days. If a drive with a history of failure is forced to absorb this heavy I/O workload:
1. Elevated Thermal and Mechanical Stress: The underlying hardware defect (such as bad sectors or degraded read/write heads) will rapidly escalate under sustained load.
2. High Secondary Failure Rate: In configurations like RAID 5, if a second drive encounters unreadable sectors during a rebuild onto a degraded target, the array hits a Double Fault or Unrecoverable Read Error (URE), taking the entire volume offline.
3. Parity Pollution: If the degraded drive drops offline intermittently during rebuild, the controller may write corrupt or incomplete parity data across the remaining members.
Standard action plan for "history of failure" alerts
Follow this step-by-step protocol to resolve the error while protecting your data.
Step 1: Immediate Verified Off-Array Backup If the array is degraded but the volume remains online and accessible:
- Immediately copy mission-critical data to an independent storage target (a separate NAS, secondary server, or cloud storage).
- Verify backup integrity using checksum validation (e.g., MD5 or SHA-256) to confirm files are readable and non-corrupt.
- Do not execute hardware diagnostics, surface scans, or stress tests before securing this backup.
Step 2: Hardware Replacement
- Identify the exact physical slot of the flagged drive via the controller management software or drive bay LEDs.
- Safely mark the drive offline within the controller interface before removal (if hot-swapping is supported), or power down the system.
- Replace with a brand-new, enterprise-grade, manufacturer-qualified drive of equal or greater capacity, matching the RPM, interface (SATA/SAS), and sector format (512e, 4Kn) of the array.
Step 3: Controlled Rebuild
- Assign the new, healthy drive as the replacement and initiate the array rebuild via the storage management console.
- Monitor controller logs throughout to verify no secondary drives report SMART or I/O threshold warnings during read operations.
Step 4: Professional Escalation
- If a second drive fails, the rebuild stalls permanently, or the array drops offline, stop all operations immediately.
- Do not force member drives online or re-initialize the RAID configuration. Proceed directly to professional data recovery services.
When to Stop DIY and consult a professional laboratory
Attempting software-based recovery or forced array re-initializations on failing server hardware can render data permanently unrecoverable.
STOP DIY RECOVERY IMMEDIATELY IF:
- Multiple member drives show offline or degraded status simultaneously.
- Mechanical scraping, clicking, or grinding sounds originate from the drives.
- The RAID controller forces the array to "FAILED" or "FOREIGN" status.
- The rebuild process freezes or encounters unrecoverable read errors (URE).
Power down the server immediately and contact professional cleanroom engineers.
When escalating to a data recovery lab, power down the array controller entirely. Label every drive with its precise bay location (e.g., Disk 0, Disk 1) to ensure the original array layout is preserved during physical disk imaging.
TL; DR: History of Failure RAID disk error is a warning sign. It can lead to further damage and data loss. Always check your Dell EqualLogic RAID array disk status to avoid any issues. Remember to keep the firmware updated to prevent errors. And set scheduled backups of your data to a secure storage device.
If you’re having problems with your Dell EqualLogic RAID array disks or want to prevent data loss, contact SalvageData at any moment. Our experts can help you with a data recovery emergency plan or restore the data from your failed disk.