Why Is There No VSS For Linux? - InformationWeek

InformationWeek is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

IoT
IoT
News
Commentary
8/11/2008
10:53 AM
Howard Marks
Howard Marks
Commentary
Connect Directly
Twitter
RSS
E-Mail
50%
50%

Why Is There No VSS For Linux?

Introduced with Windows Server 2003, the volume shadow copy service (VSS) has vastly improved the lives of those of us whose lot in life includes backing up Windows machines. By providing a standard mechanism for creating and managing snapshots, VSS lets backup applications get data-consistent backups of complex data stores like Active Directory and Exchange or Oracle databases. Why isn't there an equivalent for Linux?

Introduced with Windows Server 2003, the volume shadow copy service (VSS) has vastly improved the lives of those of us whose lot in life includes backing up Windows machines. By providing a standard mechanism for creating and managing snapshots, VSS lets backup applications get data-consistent backups of complex data stores like Active Directory and Exchange or Oracle databases. Why isn't there an equivalent for Linux?Before I really start ranting about how Linux needs a VSS equivalent, lets take a brief, and somewhat simplified, look at what VSS actually does. Look here for the official Microsoft version of how VSS works if you feel a need for details.

When a backup application needs to back up one or more resources on a server that is VSS aware, it, through its VSS Requester, sends a message to the server that enumerates the databases, file systems, and other resources to be backed up. VSS then sends a message to the VSS writer for each application to flush their buffers and make the data consistent for a snapshot. The VSS provider makes the snapshot, freezing writes for no more than 60 seconds, and flushing the file system buffers to boot. The backup program then backs up the consistent snapshot.

While Windows includes a copy on write VSS provider, VSS itself doesn't take snapshots; many disk array vendors have their own providers that allow users to capitalize on the disk array's snapshot technologies. Application vendors just need to write a VSS writer component to support a wide variety of backup applications and backup app providers can avoid the cost of developing application specific agents.

In a world without VSS, admins need to run scripts or application-specific backup or database-dump software. While this isn't a big deal for a few physical servers, it starts to become a real issue as servers, and virtual servers, proliferate.

With a VSS-enabled virtualization platform like Hyper-V or VMware VCB, with last month's update two admins can get consistent backups of VMs while backing up the entire host.

So, Linux guys: Why no VSS equivalent in your world?

We welcome your comments on this topic on our social media channels, or [contact us directly] with questions about the site.
Comment  | 
Print  | 
More Insights
The State of IT & Cybersecurity Operations 2020
The State of IT & Cybersecurity Operations 2020
Download this report from InformationWeek, in partnership with Dark Reading, to learn more about how today's IT operations teams work with cybersecurity operations, what technologies they are using, and how they communicate and share responsibility--or create risk by failing to do so. Get it now!
Slideshows
10 Cyberattacks on the Rise During the Pandemic
Cynthia Harvey, Freelance Journalist, InformationWeek,  6/24/2020
News
IT Trade Shows Go Virtual: Your 2020 List of Events
Jessica Davis, Senior Editor, Enterprise Apps,  5/29/2020
Commentary
Study: Cloud Migration Gaining Momentum
John Edwards, Technology Journalist & Author,  6/22/2020
Register for InformationWeek Newsletters
Video
Current Issue
Key to Cloud Success: The Right Management
This IT Trend highlights some of the steps IT teams can take to keep their cloud environments running in a safe, efficient manner.
White Papers
Slideshows
Twitter Feed
Sponsored Live Streaming Video
Everything You've Been Told About Mobility Is Wrong
Attend this video symposium with Sean Wisdom, Global Director of Mobility Solutions, and learn about how you can harness powerful new products to mobilize your business potential.
Sponsored Video
Flash Poll