Virtual Machine Recovery Knowledge Base

Many organisations rely on virtual machines in their data centres and implement backups through Veeam software products. Ontrack fully supports the recovery of VMware, vSphere, and Microsoft Hyper-V integrated with the Veeam environment.

If you store critical data on your virtual machine, be sure to include it in your backup routine. You may need to specify the location of the virtual machine files in your backup software to ensure they are part of scheduled backups.

Always backup your data to a secondary storage device such as an external hard drive. Backup copies of files stored on the same hard drive where the active virtual machine is located risk data loss if the hard drive fails. For safety, make multiple backups and store them on a different local server/hard drive, in the cloud or on tape. Having additional backups will help you in the event of a data loss.

Since 2008, Ontrack has performed thousands of successful data recoveries from virtual machines. Our proprietary software tools allow us to complete successful data recoveries from nearly any virtual machine, server or system; including VMware®, Microsoft® Hyper-V®, Citrix®, Linux® XEN®, and Oracle® VM.

Common problems with virtual machines include:

• Re-formatted ‘Datastore’
• Corrupted virtual disk files
• Corrupt VMFS Datastore volumes
• Deleted virtual disk files
• Deleted snapshots
• Corrupted file systems
• Traditional RAID and hardware failures

There are a number of reasons for virtual machines to slow down. While most are not related to a potential data loss you should proceed with caution and backup as soon as possible.

• Follow these steps to resolve the performance issue:
  
• Test the storage device for hardware issues and the file system for corruption.  
• Check the version of the virtual machine software on the host computer to ensure the latest version is installed.
  
• Be sure that antivirus software is properly installed and updated regularly.
• Check the virtual machine host software settings to ensure they set up properly.

Ontrack has performed thousands of successful data recoveries from servers hosting virtual machines. Our proprietary software tools allow us to complete successful data recoveries from nearly any virtual machine, server or system; including VMware®, Microsoft® Hyper-V®, Citrix®, Linux® XEN®, and Oracle® VM.

Engineers image drives and read raw data on the disk, determine what the configuration should be and then virtually rebuild the array and gain access to the storage. To do so, Ontrack has developed tools such as those that emulate the RAID controller and rebuild what is missing. The company has also developed a wealth of additional tools to accomplish such things as to prevent further writing of data onto volumes, address the complexities of virtualized files systems and more.

Ontrack’s development team continually updates its tools for the latest virtualization platforms and storage environments. Thanks to its knowledge of the various storage media, operating systems and underlying storage architectures, Ontrack offers comprehensive services for data recovery, as well as follow up services for intelligent backup and data management

With over 30 years of global experience in data management, data recovery, secure data erase, ediscovery and computer forensics, Ontrack has recovered virtualized data for thousands of enterprises.

The good news is that there are a great many ways to recover some and, in many cases, all of the lost virtual data. The first point of entry is at the storage level. It can be possible in some cases to directly recover data from physical drives by taking an image of the drives and reading whatever raw data might be available on the disk.

The next option is to attempt to recover data from the logical volumes (LUNs) or RAID. If the RAID controller is available, it can be used to track down the many slices of data spread across virtual disks. By determining what the configuration should be, engineers can virtually rebuild the array and gain access to the storage. If the RAID controller is corrupted, it may be necessary to emulate the RAID controller and rebuild what is missing.

The next level up, with each representing a higher degree of recovery difficulty, is the host file system level. In VMware this would be VMFS and in Hyper-V, NTFS or ReFS. In many cases, data isn’t available directly at the storage level. But if the right tools are used, recovery experts can trace data from the basic storage data blocks, map it to the host level and recompile it.

If that process doesn’t provide an adequate recovery, additional tools can be employed to extend further into the guest file system level. By investigating the virtual file system, data recovery specialists can sometimes find data that would otherwise be lost. Finally, it is possible to reach into the guest file level and access data lurking in application files such as SQL, Exchange, SharePoint, Oracle, Office files, ZIP files and more.