Handling Corrupted VMDK Files: A Comprehensive Guide
Virtual Machine Disk (VMDK) files are integral to VMware environments, storing all data and configurations for virtual machines. When these files become corrupted, the results can be disruptive, potentially leading to significant data loss. Fortunately, tools like VMFS Recovery provide robust solutions to address such issues efficiently.
Identifying VMDK Corruption
Before initiating a recovery, confirm the VMDK file is corrupted. Common indicators include:
- Virtual machines failing to boot.
- Error messages like "Unable to access file" or "File is missing or corrupt."
- Slow performance or system freezes during VM operations.
Steps to Recover Corrupted VMDK Files
1. Assess the Damage with Preview Tools
The VMFS Recovery tool includes features to preview data within a corrupted VMDK file, making it easier to evaluate recoverability before committing to full recovery:
- Connect the damaged VMFS datastore as a local disk or via a network location using SSH (slower) or an iSCSI interface.
- Open the datastore and mount the corrupted VMDK file in VMFS Recovery as a disk image.
- Utilize the Reader Mode to access the file instantly and check the state of the guest file system. This mode is quick and effective for initial assessments.
- If Reader Mode fails or if you need to recover deleted data, switch to Uneraser Mode.
- For extensive damage, use Full Recovery Mode. Ensure you specify the correct guest file system for accurate recovery.
Leverage the built-in preview feature to scan and display file contents, confirming that critical data is intact.
2. Recover the File
Once you’ve verified recoverability:
- Use VMFS Recovery to extract and save the repaired VMDK file to a secure location.
- For damaged VMFS datastores, confirm that the software accurately previews the most critical files before proceeding.
3. Repair Using VMware Tools
In certain cases, VMware’s built-in tools like vmkfstools can repair corrupted VMDK files.
Important: Always work on a copy of the corrupted VMDK file to avoid further damage.
vmkfstools -x check /path/to/disk.vmdk
If corruption persists, clone the file to bypass unreadable sectors:
vmkfstools -i /path/to/corrupted.vmdk /path/to/new.vmdk
Prevent Future Corruption
- Avoid abrupt shutdowns or power interruptions in your VMware environment.
- Monitor free space on VMFS volumes to ensure they don’t run out, as this can damage the VMFS structure.
- Avoid moving data across partitions. Instead, copy VMs to a new datastore, verify their functionality, and then delete the originals.
- Regularly monitor datastore health using VMware tools and perform routine maintenance.
Common Challenges and Solutions
- Corrupted Headers or Metadata: Advanced recovery tools like VMFS Recovery can bypass damaged headers and reconstruct missing metadata.
- Partial Recovery: Focus on extracting valuable data files first. Remember, it’s the data that makes a VM essential, not necessarily the VM configuration.
Conclusion
Handling corrupted VMDK files can be challenging, but with the right tools and processes, recovery is often achievable. Always start by imaging the damaged VM or VMFS volume to preserve the original state, then use tools like VMFS Recovery to assess the damage and preview recoverable data. These steps ensure minimal disruption to your VMware environment and safeguard critical data.
For additional resources and detailed instructions, visit the VMFS Recovery tutorials page.
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Posted by Administrator on Sat, 14 Dec 2024
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Resolving VMware ESX Server Datastore Detection Issues After Power Outage
Introduction
In virtualized environments, unexpected issues can arise, especially after a power outage. A common problem involves a VMware ESX Server failing to detect a datastore. This article walks you through a real-world scenario where a VMware ESX 8.0 server did not recognize a VMFS datastore after a power outage. We will discuss the problem, the root cause, and the step-by-step solution using Diskinternals VMFS Recovery.
Problem Description
A VMware ESX 8.0 server connected to a SAN storage array was shut down due to a planned power outage. After the server and storage array were brought back online, one volume remained inactive. The VMware Infrastructure Client showed the VMs on this volume as inaccessible. Despite the LUN being correctly presented, the volume appeared inactive, and the VMFS partition was not recognized by the ESX hosts. Rescanning storage adapters and refreshing the storage list did not resolve the issue.
Solution Overview
To resolve this issue, we used Diskinternals VMFS Recovery, a tool that allows the safe recovery of VMFS partitions. The process involves establishing an iSCSI connection between the SAN and a Windows PC, using VMFS Recovery to detect and recover the VMFS file system, and verifying the integrity of the recovered data.
Step-by-Step Solution
Step 1: Establish an iSCSI Connection
- Connect the SAN to a Windows PC
Use the iSCSI Initiator on your Windows PC to establish a connection with the SAN storage array. Ensure that the LUN containing the inactive volume is accessible.
Step 2: Run Diskinternals VMFS Recovery
- Launch Diskinternals VMFS Recovery
Install and open Diskinternals VMFS Recovery on the Windows PC. This software works in read-only mode, ensuring that your production data remains intact.
- Detect the VMFS File System
Option A: Fast Scan
Choose the LUN from the list of available drives. Use the "Reader" or "Fast scan - Uneraser" modes to quickly scan the iSCSI volume.
If VMFS Recovery detects the VMFS file system, you can proceed to browse the recovered data.
Option B: Full Recovery
If the VMFS file system is not detected in the previous step, select "Full Recovery -> VMFS" mode.
This method is more thorough but takes longer to complete.
Step 3: Browse and Recover Data
- Mount the Recovered VMDK File
Once the recovery process is complete, browse the recovered data. Locate the VMDK files corresponding to your VMs.
Right-click on the required VMDK file and select the "Mount as Disk" option. This action will mount the VMDK file as a disk image on your Windows PC.
Refer to the complete guide on previewing recovered VMDK files at this link.
Step 4: Verify Data Integrity
- Open the Mounted VMDK File
Open the mounted VMDK file in "Reader" mode within Diskinternals VMFS Recovery.
- Preview and Verify Data
Use the built-in preview feature to check the integrity of the recovered data. Ensure that the files are intact and accessible.
If the data is valid, consider purchasing a registration key from this link to save the recovered files.
Conclusion
Recovering an inaccessible VMFS volume after a power outage can be daunting, but with the right tools and procedures, the process becomes manageable. By following this guide and using Diskinternals VMFS Recovery, you can safely recover your data without risking further loss. Always remember to verify the integrity of your data before proceeding with any major recovery operations.
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Posted by Administrator on Wed, 28 Aug 2024
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VMDK Recovery Tool
VMDK files are crucial repositories of data for virtual machines. However, various factors can lead to the loss or corruption of these files, rendering the associated virtual machines inaccessible.
The good news is that losing VMDK data doesn't have to be catastrophic. With the right tools, you can recover these files and restore your virtual machines to full functionality. Using a professional recovery tool ensures a higher chance of successful restoration.
VMFS Recovery stands out as the preferred VMDK Recovery Tool for experienced PC users seeking to recover their virtual machine files from VMware host servers. This software is compatible with all versions of Windows OS and Windows Server, offering comprehensive recovery capabilities from any type of disk.
VMFS Recovery | VMDK Recovery Tool
When it comes to safeguarding important files, no level of caution is ever enough. Unexpected events like power outages, system crashes, hard disk failures, and other unforeseen data loss scenarios can strike at any time. In such situations, having reliable data recovery tools becomes crucial.
For those working with virtual disks and machines, ensuring data integrity is paramount. It's essential to have robust backup and recovery solutions that can handle virtual environments effectively.
VMFS Recovery is a specialized VMDK Recovery Tool designed to tackle various virtual hard disk data loss scenarios, including recovering deleted flat files in VMware environments. It restores critical files necessary to repair damaged or corrupted virtual machines, ensuring they can be operational again. Additionally, the tool can access and mount inaccessible VMFS volumes.
Tips: More info about VMDK file types
VMFS Recovery: VMDK Recovery Tool Features
Discover the standout features of DiskInternals VMFS Recovery, the premier VMDK Recovery Tool designed for Windows OS.
- Smooth Recovery Process: DiskInternals VMFS Recovery includes a built-in Recovery Wizard that guides users through each step of the recovery process, ensuring a seamless experience even for non-experts.
- Designed for VMware VMFS File System: Specifically engineered to read and recover files from VMware's VMFS file system, making it an ideal tool for recovering data and files from virtual machines hosted on VMware platforms such as vSphere or ESXi.
- Recovers from Corrupted or Healthy VMFS-formatted Drives: Capable of accessing and recovering data from corrupted VMFS-formatted drives, enabling recovery even when the virtual drive fails to mount.
- Recovers VMDK Images on VMware vSphere, ESXi/ESX Servers: Supports VMFS partitions created on vSphere and ESX/ESXi servers, including VMFS3, VMFS5, and VMFS6. Recovers files and partitions up to 64 TB in size, with support for Unicode file names in VMFS5 and VMFS6, and multi-level folders.
- Recovers VMFS Drives on Corrupted and Inaccessible Hard Drives: Renowned for its high success rate in recovering files from damaged drives, particularly effective when utilizing Full Recovery mode to scan corrupted disks, examining VMware VMFS datastores, disks, volumes, and RAID (if used).
- Automated Recovery with Step-by-Step Wizard: Features an intuitive Recovery Wizard that simplifies the recovery process. Offers Fast Recovery Mode for quick file retrieval and Full Recovery Mode for comprehensive data restoration, including repair of bad sectors and corrupted data stores.
- Mount Virtual Drives as Local Disks: Enables mounting of virtual drives as physical disks accessible via Windows File Explorer, facilitating easy preview and access to recovered files.
- RAID Recovery Support: Includes comprehensive RAID recovery tools, compatible with RAID JBOD, 0, 1, 1E, 0+1, 1+0, 4, 5, 50, 5EE, 5R, 6, and 60 configurations for VMFS drives.
- Remote Online Recovery: Allows seamless data recovery operations on remote servers without requiring shutdowns, ensuring minimal disruption during recovery processes.
- Recovers VMDK Images from VMware ESX/ESXi Server-formatted Disks: Recovers VMDK image files from disks previously formatted by VMware ESX/ESXi servers with high success rates.
- Export Recovered Files and Folders: Provides options to export recovered data to local or remote locations, including FTP, giving users flexibility in data retrieval and storage.
- Windows OS Restrictions Bypassed: Ensures robust data recovery by bypassing Windows OS limitations without compromising system privacy or security settings.
DiskInternals VMFS Recovery is a top-tier solution for VMware VMDK recovery, boasting up to 99% efficiency across various data loss scenarios. With its user-friendly Recovery Wizard and extensive feature set available for free, it stands as an indispensable tool for virtual machine data recovery.
Tips: How to recover information from inside *.VMDK files
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Posted by Administrator on Fri, 28 Jun 2024
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VMFS Recovery
Introduction
VMFS (Virtual Machine File System) recovery is a critical process aimed at restoring data stored within the VMFS file system, a specialized file system developed by VMware for use in ESX servers and vSphere virtualization environments. Designed primarily for the storage of virtual machine disk images, VMFS is optimized to manage a limited number of large files. This article delves into the intricacies of VMFS recovery, detailing the architecture, metadata, and recovery approaches.
VMFS Architecture
VMFS is designed to store disk images for ESX virtual machines, focusing on optimizing performance for a small number of large files. Disk space for a VMFS volume can be provided by a single disk or multiple disks, often organized as hardware RAID arrays. The VMFS driver consolidates these available disk space extents into a JBOD (Just a Bunch Of Disks) configuration, enhancing data management and retrieval.
VMFS Metadata
Metadata in VMFS is critical for file organization and retrieval. It is typically located at the beginning of the VMFS volume or, in the case of multiple extents, at the start of the first extent. VMFS metadata includes inodes, which store file information, directories, and repositories for small files.
To store disk images of virtual machines efficiently, VMFS employs 1 MB clusters, a cluster size larger than that used by most common file systems. As a result, without specific optimization, even small files occupy a minimum of 1 MB. However, with VMFS version 5 and beyond, files smaller than 1 KB are stored directly within their corresponding inodes, similar to how resident files are managed in the NTFS file system. For files larger than 1 KB, VMFS creates a single large file and divides it into 8 KB clusters, which are then utilized to store small files. These approaches effectively reduce disk space usage for small files. Notably, directories, regardless of their size, always occupy at least 1 MB of disk space.
It's important to mention that all VMFS metadata is typically contained within the first 3 to 5 GB of the VMFS volume. Consequently, a comprehensive VMFS structure recovery can be achieved by scanning only the initial 5 GB of the VMFS volume.
VMFS Recovery Approaches
VMFS recovery is a multifaceted process that aims to restore data from VMFS volumes, even in complex scenarios requiring preliminary RAID recovery. The VMFS recovery capability offered by Diskinternals VMFS Recovery© is instrumental in this regard, accommodating both straightforward and intricate recovery cases.
RAID Configuration Recovery: Since VMFS is often implemented on one or multiple hardware RAID configurations, the initial step in VMFS recovery is to recover the correct RAID storage configuration. This is achieved by detecting the configuration of one or more RAID arrays that compose a VMFS volume. The RAID recovery feature, known as RAID Wizard, is a step-by-step guide for this purpose.
VMFS File System Recovery: Once VMFS extents are correctly assembled, the process of VMFS file system recovery can commence on the reconstructed RAID disk volume. The reconstructed RAID disk, along with any automatically detected volumes it contains, is added to the disk list, marked in red to facilitate navigation.
Manual Assembly: In cases where the RAID volume is not detected automatically, manual assembly of the RAID volume from the physical volumes or disk images is possible. This is accomplished by running the RAID Wizard and specifying the necessary configuration for the RAID disk containing the VMFS volume.
Scanning for VMFS Volume: In situations where the VMFS volume is not initially detected, a scan can be initiated. VMFS Recovery is instructed to search for viable VMFS data on the disk, offering an inclusive approach to data retrieval.
In conclusion, VMFS recovery is a crucial process for the retrieval of data from VMFS volumes, whether the circumstances are straightforward or complex. Diskinternals VMFS Recovery© provides the necessary tools and guidance to ensure successful VMFS recovery, encompassing RAID configuration recovery, VMFS file system recovery, manual assembly, and comprehensive scanning approaches.
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Posted by Administrator on Mon, 16 Oct 2023
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New release of VMFS Recovery: v.4.10.1.3
Added BtrFS support.
A B-Tree file system, a perspective file system used by Linux OS, gains a lot of recognition from manufacturers of NAS devices.
A lot of new NAS models from Synology are using BtrFS by default or can be formatted to this file system. A software NAS solution: FreeNAS also uses BtrFS.
Windows 11 compatible
After the release of Microsoft Windows 11, we have performed extensive testing and make sure that VMFS Recovery is ready to work under the fresh and latest Windows OS release.<.p>
Minor but important changes in the interface and software logic
At last, the boss has approved renaming the “Hard Drives” section to “Partitions”. It was really strange to see numerous volumes and disk images there, and a separated “Physical Drives” section below.
We have also changed a warning during software exit confirmation, now it warns that all the scan results will not be saved.
Improvements in EXT, ZFS, NTFS and VMFS recovery modules
Cumulative minor improvements update for specified file systems. Access speed was also improved a bit.
Feel free to download VMFS Recovery™ 4.10.1.3
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Posted by Administrator on Mon, 18 Oct 2021
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