Cisco RAID 5 servers are widely used by large corporate companies for storing virtualized environments, databases, and mission-critical applications. However, when multiple drives fail and an incorrect RAID rebuild is initiated, it can overwrite existing data, making recovery extremely complex.
This case study details how we successfully recovered critical VMDK virtual machine files and corporate databases from a Cisco RAID 5 server with 24 Seagate disks, after an accidental rebuild overwrote key RAID metadata and file structures.
As Glasgow Data Recovery, Scotland’s oldest and best data recovery company, we have 25 years of experience using RAID reconstruction, VMware VMDK file recovery, and forensic-level data extraction techniques to restore lost corporate data.
The Challenge: Cisco RAID 5 Failure After Accidental Rebuild
A large corporate company contacted us after their Cisco RAID 5 server failed, with the following issues:
- Two disks failed, putting the RAID in degraded mode.
- A rebuild was attempted using the wrong replacement disk.
- The incorrect RAID rebuild caused data overwrites, corrupting virtual machines.
- The server contained business-critical databases stored as VMDK virtual disk files.
- The system would no longer boot, and IT support could not recover the data.
Since RAID rebuilds modify parity and existing data structures, an immediate expert-level recovery solution was required to prevent permanent data loss.
Diagnosis & Evaluation
When the Cisco RAID 5 server (24-disk setup) arrived at our cleanroom facility, we conducted a full RAID and file system diagnostic. Our findings:
- Two disks had initially failed, leading to RAID degradation.
- The RAID 5 array had been rebuilt with the wrong disk, causing further corruption.
- VMware VMDK files were partially overwritten, preventing the virtual machines from booting.
- File system corruption (NTFS/VMFS) – Making the stored corporate databases inaccessible.
Since continued RAID rebuild attempts could cause further data loss, we prioritised manual RAID reconstruction and virtual machine recovery.
The Recovery Process
1. Cloning & Imaging All RAID 5 Disks to Prevent Further Data Loss
To preserve the recoverable data, we:
- Created forensic sector-by-sector clones of all 24 RAID disks.
- Used specialized RAID recovery tools to extract readable sectors and bypass overwritten areas.
2. Manually Rebuilding the RAID 5 Array & Restoring Overwritten Data
Since RAID metadata was overwritten, we:
- Analyzed parity distribution and manually reconstructed the RAID array.
- Used advanced RAID analysis to detect previous configurations before the accidental rebuild.
- Rebuilt missing RAID headers and restored file system structures.
3. Extracting & Repairing VMware Virtual Machines (VMDK Recovery)
Once the RAID structure was successfully rebuilt, we:
- Recovered all corrupted VMDK virtual disk files from the VMFS partition.
- Repaired VMDK headers to restore access to the corporate databases.
- Extracted SQL databases, transaction logs, and user data from within the virtual machines.
4. Extracting & Verifying Corporate Database Files
Once the virtual machines were restored, we:
- Recovered all corporate database files, financial records, and operational data.
- Repaired SQL database indexes and transaction logs.
- Transferred the fully restored data to a secure external RAID backup system.
The Results: 95% Data Recovery Success
Thanks to our RAID reconstruction and VMware VMDK file repair techniques, we successfully recovered 95% of the corporate company’s lost data, including:
✅ VMware ESXi virtual machines fully restored
✅ SQL databases and business-critical applications recovered
✅ Corporate financial records, client data, and operational files retrieved
The corporate company was able to restore their entire business database infrastructure, preventing financial and operational losses.
Why Choose Us?
With 25 years of experience and tens of thousands of successful RAID recoveries, we are Scotland’s leading server and RAID data recovery specialists. Our expertise includes:
✔ Cisco RAID 5 failure recovery & overwritten data reconstruction
✔ VMware, Hyper-V, and virtual system restoration
✔ SQL database repair & corporate data retrieval
✔ Secure & confidential enterprise data recovery services
If your RAID 5 server has been accidentally rebuilt, is suffering from multiple drive failures, or is preventing access to critical corporate data, stop using the system immediately and contact us for expert Cisco server recovery.