Server cannot see the RAID volume
The controller lists drives but no virtual disk, or the operating system no longer detects the expected block device.
Review this failure →Server recovery
Recover business data when a server loses its storage, volume, or application path.
A server failure can begin at the controller, RAID, filesystem, virtual disk, database, or application layer. ADR identifies where access was lost before choosing a recovery path.
Have the server model, controller, member count, operating system, symptoms, and actions already attempted available.
Since 1998Business-critical recovery
Layer-by-layer diagnosisController through application
Remote or in-labChosen for the failure
Priority-data verificationFiles, databases, and VMs
Recognize the failure
The server may be running while the business data remains inaccessible.
The visible symptom does not always identify the failed layer. A missing database can originate in the application, filesystem, virtual disk, RAID, controller, or physical members.
Controller configuration changed
HPE Smart Array, Dell PERC, or another controller reports foreign, missing, unconfigured, or degraded storage.
Dell PERC guidance →Server boots but applications fail
SQL, accounting, medical, production, or other business systems cannot open their databases or data stores.
Database recovery options →Database recovery pending or suspect
The database engine cannot complete recovery after storage went offline, returned corrupt data, or came back in a different state.
SQL recovery-pending guidance →Operating system will not boot
The boot path, filesystem, logical volume, or backing RAID is missing even though the server hardware powers on.
Multiple members dropped
The server storage exceeded normal fault tolerance during a rebuild, power event, or period of degraded operation.
Multiple-member guidance →A controlled recovery path
Restore the storage foundation before repairing what depends on it.
- 1
Establish the failed layer
Review controller, RAID, volume, filesystem, virtualization, database, and application symptoms.
- 2
Protect the sources
Preserve member order and image unstable storage to separate destinations before reconstruction.
- 3
Reconstruct the data path
Recover the RAID or volume, then evaluate filesystems, virtual disks, and databases in the correct order.
- 4
Verify business data
Check the files, databases, virtual machines, and application data that matter to the organization.
Choose the recovery location and scope
Remote when the storage is stable. Protected imaging when it is not.
Logical and configuration-related cases may qualify for technician-led remote recovery when suitable access and destination storage are available. Unstable or mechanically compromised members require imaging or physical escalation.
Follow the failure to the right service
Choose the path that matches the failed layer.
Storage failures often cross controller, RAID, filesystem, virtualization, and application boundaries. These services connect the next layer without asking the failed system to make another decision.
Failure-specific guidanceRAID recoveryOffline arrays, failed rebuilds, missing virtual disks, and multiple-member failures.Review this recovery path →Custody-sensitive optionRemote RAID recoveryTechnician-led diagnosis and reconstruction when the sources can safely remain onsite.Review this recovery path →Application-data pathSQL database recoveryWhen storage is accessible again but business databases will not attach or recover.Review this recovery path →
Before another repair attempt
Describe the server, storage, and business impact.
ADR will help determine whether the case begins with remote diagnosis, protected imaging, RAID reconstruction, filesystem recovery, or application-data validation.