What Is VSS and How To Troubleshoot VSS Errors

You could paint two pictures about Microsoft and they would both be true. Although Microsoft can certainly boast of bestowing an incredible array of technological gifts onto the business world, their products can, at times, be painstaking to deal with as well. This contradiction is never more apparent than with Microsoft VSS.

What is VSS?

Developed by Microsoft, Volume Shadow Copy Service (VSS) enables backup applications to safely back up locked and open files. It captures and creates snapshots of your system called shadow copies. This includes copies of MS Exchange, SharePoint and Hyper-V data.

How VSS works?

The powerful yet complex VSS infrastructure is what makes VSS good (and bad) for your data center. It works primarily around three components:

  • Requester – This is an application that requests (from a provider) the creation of a snapshot. Typically, VSS requesters are the Windows Server Backup utility and the System Center Data Protection Manager applications, as well as all backup applications that run on Windows.
  • Provider – This component provides the VSS service by creating and maintaining shadow copies.
  • Writer – VSS providers notify VSS writers so they can alert the application to prepare for snapshotting. It guarantees that you have a consistent data set to back up.

The benefits of VSS

The VSS infrastructure works in unison and allows businesses to ensure backup takes place quietly and seamlessly. The shadow copies are used to:

  • Recover lost data quickly
  • Perform disk-to-disk backups
  • Move archived data to another hard disk

What are VSS errors?

VSS errors reveal the not-so-pretty face of Microsoft. For example, when a snapshot is created, VSS writers are called in. However, if any of the writers encounter an error, the entire backup task fails.

A common cause of VSS errors is the use of multiple backup solutions. Multiple backup solutions undermine your recovery since each solution may want to use a different VSS driver. Moreover, they give rise to confusion about which backup solutions should protect which data set.

Tired of sifting through multiple applications? Learn more about Unitrends Unified BCDR.

The impact of VSS errors

VSS errors are troublesome to varying degrees, depending on how they manifest.

Businesses sacrifice a chunk of admin time and productivity to resolve VSS errors. It leads to wasted time and inefficiencies, forcing IT to perform low-value, manual troubleshooting tasks while dealing with an unpredictable backup system. It ultimately impacts their RTO strategy, putting their business at risk.

How to troubleshoot VSS errors

Fortunately, you don’t have to hit the panic button every time you encounter a VSS error. Follow these VSS troubleshooting steps to ensure business continuity.

  1. Review the Logs located in C:\PCBP\Catalog.dir and C:\PCBP\Logs.dir.
  2. Check the Event Logs (Application and System are common).
  3. Determine if any VSS writers have failed.
  4. Review the Task Scheduler for jobs that may be running when the backup application runs.
  5. Check that the schedules for SQL Maintenance and Exchange Maintenance plans do not conflict with the schedules for the backup application.

Automated detection and remediation of VSS errors

Designating a technician to solely manage backup failures caused by VSS errors is a colossal waste of resources that could be better spent on projects to help grow your business and improve the experience for both end users and customers.

Introducing Unitrends Helix — an intelligent engine that automates monitoring and proactively remediates issues with VSS services and third-party VSS providers that wreak havoc on backups. IT professionals can now avoid all the heavy lifting and stress that comes with VSS errors.

Start your data protection on a perfect note by getting the technology your business and end users deserve, so your time can be better spent growing your business and not troubleshooting backups.

Schedule a demo today!


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