Recover Vmfs Volume
| Symptom | Likely Cause | | :--- | :--- | | Datastore shows as "Unmounted" or "Inaccessible" | Storage connection issue or improper removal. | | Datastore shows as "Corrupt" or has a different capacity | Metadata corruption or partition table damage. | | Datastore is "Missing" after a SAN reboot | LUN masking/zoning changed or device reservation lost. | | Accidentally formatted the LUN as a different filesystem | Human error (most common). |
If the datastore is visible but won't mount due to a minor header issue:
Mount it temporarily using: esxcli storage vmfs snapshot mount -l "DatastoreName" . recover vmfs volume
Ensure all HBAs and cables are secure.
Specialized recovery tools can scan the raw sectors of the LUN to find VMDK (Virtual Machine Disk) headers. | Symptom | Likely Cause | | :---
Armed with this knowledge, John implemented additional redundancy and safeguards to prevent similar incidents in the future, including:
A VMFS volume typically becomes inaccessible due to a few specific scenarios. The volume might be unmounted, or the partition table could be corrupted. In other cases, a storage snapshot might be viewed as a "snapshot LUN" by ESXi, requiring a resignation. Identifying the root cause—be it human error, a failed RAID controller, or an interrupted firmware update—is the first step in the recovery process. Phase 1: Initial Health Check | | Accidentally formatted the LUN as a
With the business services still down, John knew he had to act fast. He decided to use a third-party tool, RDMp (Raw Device Mapping partition recovery), to recover the VMFS volume. He had used this tool before in similar situations, and it had always yielded good results.