How do I check my VM backup?

Backing up virtual machines is critical to prevent data loss and ensure business continuity. This guide will teach you several methods to verify your VM backups completed successfully, so you can rest assured your data is protected.

How do I check my VM backup?

Why verifying backups is essential

Virtual machine (VM) backups provide an essential way to recover VMs and data in event of hardware failure, data corruption, accidental deletion, malware, and more. However, simply running backups is not enough. You must also confirm backups complete successfully and data can be recovered when needed.

Some key reasons it is vital to check VM backups include:

  • Identify failed or incomplete backups to fix issues
  • Ensure ability to restore VMs and data if needed
  • Validate recovery point objectives (RPOs) are met
  • Adhere to compliance and regulations for backup verification
  • Avoid unexpected data loss from backup failures

In short, routinely verifying VM backups works prevents nasty surprises that could disrupt operations and ensures your data protection strategy delivers the resilience your business needs.

View backup logs and reports

Most enterprise backup solutions provide logs and reports detailing the status of VM backup jobs. Review these logs and reports on a regular basis to catch any backup failures, errors, or warnings requiring attention.

Common VM backup reports and logs to check include:

  • Backup job status – Summary reports indicating whether recent backup jobs completed successfully or failed.
  • Backup errors and warnings – Logs noting issues, failures, or warnings encountered during backup processes.
  • Backup performance – Reports on backup job duration, data throughput, compression ratios, etc.
  • Backup catalog – Listing of all VMs registered for backup and metadata like last backup date.

Set calendar reminders to examine logs and reports periodically if the backup software does not already automatically alert on failures. Many backups can fail without notifications unless backup reporting is checked.

Mount backed up VM virtual disks

One direct way to validate VM backups is to mount the virtual disks (.vmdk files) from a recent backup. Mounting attaches the backup virtual disk files to an ESXi host or recovery VM so you can power on and examine the files.

Steps to mount backed up VM disks include:

  1. Locate the recent VM backup within the backup repository
  2. Note the path to the .vmdk files for the backed up VM
  3. Use VMware Horizon tools to attach the read-only .vmdk files to a VM or ESXi host
  4. Power on the VM and validate accessible files as needed
  5. Unmount disks when verification complete

By directly mounting backups as virtual disks, you can browse files like a live VM to ensure the backup contains the expected OS, data files, databases, etc.

Test restoring VMs or files

The most definitive validation of VM backups is to perform test restores of full VMs or individual files. Regular test restores confirm:

  • Backups contain the necessary files – Only way to truly verify backed up file integrity
  • Restores work properly – Tests entire workflow from locating backups to recovery
  • RPO objectives are met – Validates ability to restore VMs to recent enough point in time
  • Recovery times – Determine if recovery speed meets RTO needs

Ideally test restores should be run:

  • Using different backup points – Don’t just test the latest backup each time
  • On different VMs – Check more than just one VM to confirm broad backup integrity
  • On approximately a monthly basis – Frequent enough to catch issues over time

Save restore test results and learnings as evidence of diligent backup verification.

Automate backup health monitoring

Manually checking backup logs and running test restores provides definitive one-time validation but quickly becomes tedious and time consuming.

For ongoing automated peace of mind, consider backup monitoring and analytics tools provided by many major vendors. Features may include:

  • Automatic daily backup success/failure email alerts
  • Consolidated dashboard highlighting backup verification status across environments
  • Historical charts and trends on backup frequencies, times, and compression rates
  • Automated comparision of recent backup integrity vs. set benchmarks
  • Built-in reminder notifications to conduct test restores

Enabling these automated backup health checks provides continuous insight into VM backup status while reducing the manual checking burden. Budgeting for premium vendor tools is a wise investment for valuable data protection assurance they facilitate.

Key takeaways

  • Check backup logs/reports – Primary way to monitor latest status and be alerted to failures
  • Mount backup disks – Directly validate files are present by mounting backups
  • Test restore VMs/files – Definitive validation backups contain expected data
  • Enable monitoring tools – Automate continuous backup & restore validation

Do not “set and forget” VM backups after initial configuration. Instead, make backup health monitoring a routine practice via combination of manual and automated validation checks. Treat backup verification as vital to realizing the full value of VM data protection investments.


Routinely verifying VM backups provides necessary assurance your business can recover critical systems and data when disaster strikes. Save costs and headaches by catching backup failures early and keeping data restoration skills sharp via regular testing.

Make backup validation standard practice across technology teams. Empower personnel to monitor VM backup health via tools providing transparency into successes, failures, warning signs requiring attention, and opportunities to improve data protection through learnings from restore tests cases. Make checkups easy via automation.

Validating VM backups takes a bit more effort up front but delivers immense long-term peace of mind. Data is irreplaceable, so invest appropriately in its protection and confirm backups continually capture your vital information.

Frequently Asked Questions

Q: How often should you check VM backups?
A: Check backup logs at least daily for failures and warnings. Test restores every month. Enable automated alerts.

Q: Can you mount a VM backup?
A: Yes, VM backup tools allow mounting virtual disks to validate contents. Attach read-only to prevent changes.

Q: What reports indicate backup verification status?
A: Key reports include backup job status, errors/warnings, catalog listings, performance trends. Check at least weekly.

Q: Should you restore backups to original or alternate locations?
A: Restore to alternate locations first during tests to avoid overwriting current VMs and data.

Q: What tools automatically verify VM backup integrity?
A: Monitoring solutions from major vendors offer health dashboards, alerting, analytics on backup status.

Q: How long should you retain VM backup verification records?
A: Retain validation records as long as backups. E.g. if backups stored for 1 year, keep validation results for 1 year.

Q: What steps validate backup chains are intact?
A: Restore various points from multiple recovery points. Test oldest to newest backup periodically.

Q: Should you test restore encrypted VM backups separately?
A: Yes, test decryption process works too. Encrypted, compressed backups add risk points.

Q: What tools compare VM disk contents vs. backups?
A: Third-party comparison tools like Updraft Direct can hash-check disk vs. backup differences.

Q: Where should VM backup verification tasks be documented?
A: Document verification standard procedures in company security policies, disaster recovery plans.

Q: How often should you test RTO/RPO benchmarks?
A: Test meeting RTO/RPO goals each time major backups restored during quarterly or annual tests.

Q: What metrics indicate VM backup & restore performance?
A: Key metrics are backup duration, compression ratio, recovery time, amount data processed over time.

Q: What data helps calculate ideal VM backup storage needs?
A: Historical size occupied, deduplication/compression ratios, retention policies, growth rate.

Q: Should you verify integrity of synthetic full backups separately?
A: Yes. Seed incremental chains can propagate issues until fulls hit. Test full integrity quarterly.

Q: How often should VM high availability measures be tested?
A: Annually failover/fallback HA VMs under load to confirm availability, performance metrics.

Q: Should VM backup verification involve compliance teams?
A: Yes, keep auditors aware of verification results as evidence of diligent controls.

Q: What aspects of VM backup DR plans should be tested?
A: Test all components – communications, roles, software capabilities, capacity, procedures.

Q: Where can you find documentation on major VM backup products?
A: Vendor sites detail best practice guides, technical manuals, configuration notes.

Q: What skills are needed to adequately verify VM backups?
A: Backup software, virtualization platform expertise. Plus storage, networking, security knowledge.


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