Case Study

Successful Recovery of 33TB Data from NAS Email Server

The loss of critical business information hampered continuity and posed a potential impact on revenue.

Client Background

The organization, a leading IT company in India specializing in enterprise cloud solutions, focuses on collaboration, network and cloud security, and disaster recovery. It relied on a NAS email server with a 66TB storage capacity to archive emails and facilitate seamless email search, retrieval, and export operations.

Addressing Key Challenges in Data Recovery

The Barracuda® Message Archiver, acting as the NAS email server, was set up with 26 SATA HDDs (Western Digital and Hitachi), each with a 3TB capacity, totaling 33TB of archived email data along with other files.
When some of the hard drives started to fail, the storage administrator replaced them to restore the RAID array's performance. However, the RAID controller couldn’t recognize the original configuration and instead marked the new drives as a foreign configuration. As a result, the rebuild process failed, and the Barracuda® Message Archiver couldn’t detect or access the data.
Even after replacing the message archiver and using a new one, the drives were still showing as a foreign configuration. This left the 33TB of archived email data completely inaccessible, and further attempts to rebuild the array risked permanent data loss.

Business Impact

The failure of the Barracuda® Message Archiver (model 1050) revoked organization-wide access to crucial information stored in the archived mailboxes. This posed a significant setback for the business, potentially affecting sales, business intelligence, and even strategic interests.
The company was at risk of losing massive data assets — including 33TB of critical archived email data — that had been accumulated and refined over several years.

Data Recovery Actions & Approach

After evaluating various software and service options, the company’s IT team reached out to a trusted data recovery provider for a solution to this significant data recovery challenge and to help them get back to business.
The client chose Stellar for its strong R&D team, extensive experience in handling complex RAID failure cases, and its Class 100 cleanroom infrastructure, which provided the confidence needed to address the issue effectively.

Stellar assigned a dedicated team of 3 R&D experts and 2 data care professionals to tackle the data recovery project. The team followed a structured approach to retrieve the data:

1. Lab examination of Barracuda® Message Archiver (model 1050)

Examination of Hard Disk Drives for functionality (working/non-working); found 1 hard drive to be non functional with physical damage (clicking noise)
A few other hard drives were diagnosed with functional issue of delayed reading
These multiple hard drive functional issues were the cause of RAID failure and data inaccessibility.

2. Hard drive dismantling and head assembly replacement in state-of-the-art Class 100 cleanroom

Requested tampering permission from client organization to check physical condition of the platter and head assembly.
The head assembly was found broken. Also, there were light visible scratches on the platter which might skew the odds of recovering data from this particular hard drive.
Nonetheless, a new head assembly was transplanted on the hard drive to evaluate feasibility of salvaging the data.
The hard drive remained inaccessible even after successful head assembly replacement. Due to scratches on the platter, this data was irretrievably lost.

3. Disk cloning and process to determine RAID configuration parameters

A team of data care experts cloned the recoverable hard drives by using a proprietary cloning software.
The R&D team connected these 25 cloned hard drives to a specialized server to get access to individual drives in order to determine key RAID array logical parameters viz. strip size, data flow pattern, RAID configuration and parity flow information.
Upon examining the 25 individual drives, the R&D team found Ext4 file system structure with RAID 60 (RAID 6+0) configuration having backward dynamic parity flow with strip sizes as 128 sectors and undefined strip size based upon the number of drives used in the RAID array.

4. Deep scanning to retrieve data

Stellar data care experts used proprietary data recovery software on this single clone to recover the requisite data
The end result was successful recovery of 100% data from the crashed Barracuda® Message Archiver 1050.

Result

Our RAID data recovery experts used proprietary data recovery software on the cloned drive to recover the required data. The data was recovered intact, with 100% integrity in its original form, as verified and attested by the client.

The result was the successful recovery of 100% of the data from the crashed NAS email server (Barracuda® Message Archiver 1050). This remarkably fast turnaround and service quality helped the client organization quickly recover from the downtime and resume normal business operations.

You can also check our other case studies for more insights into our data recovery services.