Enabling The Green and Virtual Data Center

Greg Schulz

Subscribe to Greg Schulz: eMailAlertsEmail Alerts
Get Greg Schulz via: homepageHomepage mobileMobile rssRSS facebookFacebook twitterTwitter linkedinLinkedIn

Blog Feed Post

RIP Windows SIS (Single Instance Storage), or at least in Server 2016

RIP Windows SIS (Single Instance Storage), or at least in Server 2016

RIP Windows SIS, or at least in Server 2016

server storage I/O trends

I received as a Microsoft MVP a partner communication today from Microsoft of a heads up as well as pass on to others that Single Instance Storage (SIS) has been removed from Windows Server 2016 (Read the Microsoft Announcement here, or below). Windows SIS is part of Microsoft's portfolio of tools and technology for implementing Data Footprint Reduction (DFR).

Granted Windows Server 2016 has not been released yet, however you can download and try out the latest release such as Technical Preview 4 (TP4), get the bits from Microsoft here. Learn more about some of the server and storage I/O enhancements in TP4 including storage spaces direct here.

Partner Communication from Microsoft

Partner Communication
Please relay or forward this notification to ISVs and hardware partners that have used Single Instance Storage (SIS) or implemented the SIS backup API.

Single Instance Storage (SIS) has been removed from Windows Server 2016
Summary:   Single Instance Storage (SIS), a file system filter driver used for NTFS file deduplication, has been removed from Windows Server. In Dec 2015, the SIS feature has been completely removed from Windows Server and Windows Storage Server editions.  SIS was officially deprecated in Windows Server 2012 R2 in this announcement and will be removed from future Windows Server Technical Preview releases.

Call to action:
Storage vendors that have any application dependencies on legacy SIS functions or SIS backup and restore APIs should verify that their applications behave as expected on Windows Server 2016 and Windows Storage Server 2016. Windows Server 2012 included Microsoft’s next generation of deduplication technology that uses variable-sized chunking and hashing and offers far superior deduplication rates. Users and backup vendors have already moved to support the latest Microsoft deduplication technology and should continue to do so.

SIS was developed and used in Windows Server since 2000, when it was part of Remote Installation Services. SIS became a general purpose file system filter driver in Windows Storage Server 2003 and the SIS groveler (the deduplication engine) was included in Windows Storage Server. In Windows Storage Server 2008, the SIS legacy read/write filter driver was upgraded to a mini-filter and it shipped in Windows Server 2008, Windows Server 2012 and Windows Server 2012 R2 editions. Creating SIS-controlled volumes could only occur on Windows Storage Server, however, all editions of Windows Server could read and write to volumes that were under SIS control and could restore and backup volumes that had SIS applied.

Volumes using SIS that are restored or plugged into Windows Server 2016 will only be able to read data that was not deduplicated. Prior to migrating or restoring a volume, users must remove SIS from the volume by copying it to another location or removing SIS using SISadmin commands.

The SIS components and features:

  • SIS Groveler. The SIS Groveler searched for files that were identical on the NTFS file system volume. It then reported those files to the SIS filter driver.
  • SIS Storage Filter. The SIS Storage Filter was a file system filter that managed duplicate copies of files on logical volumes. This filter copied one instance of the duplicate file into the Common Store. The duplicate copies were replaced with a link to the Common Store to improve disk space utilization.
  • SIS Link. SIS links were pointers within the file system, maintaining both application and user experience (including attributes such as file size and directory path) while I/O was transparently redirected to the actual duplicate file located within the SIS Common Store.
  • SIS Common Store. The SIS Common Store served as the repository for each file identified as having duplicates. Each SIS-maintained volume contained one SIS Common Store, which contained all of the merged duplicate files that exist on that volume.
  • SIS Administrative Interface. The SIS Administrative Interface gave network administrators easy access to all SIS controls to simplify management.
  • SIS Backup API. The SIS Backup API (Sisbkup.dll) helped OEMs create SIS-aware backup and restoration solutions.


What this all means

Like it or not, SIS is being removed from Windows 2016 replaced by the new Microsoft deduplication or data footprint reduction (DFR) technology.

You have been advised...

RIP Windows SIS

Ok, nuff said (for now)


Greg Schulz - Author Cloud and Virtual Data Storage Networking (CRC Press), The Green and Virtual Data Center (CRC Press) and Resilient Storage Networks (Elsevier)
twitter @storageio

All Comments, (C) and (TM) belong to their owners/posters, Other content (C) Copyright 2006-2016 Server StorageIO(R) and UnlimitedIO All Rights Reserved

Read the original blog entry...

More Stories By Greg Schulz

Greg Schulz is founder of the Server and StorageIO (StorageIO) Group, an IT industry analyst and consultancy firm. Greg has worked with various server operating systems along with storage and networking software tools, hardware and services. Greg has worked as a programmer, systems administrator, disaster recovery consultant, and storage and capacity planner for various IT organizations. He has worked for various vendors before joining an industry analyst firm and later forming StorageIO.

In addition to his analyst and consulting research duties, Schulz has published over a thousand articles, tips, reports and white papers and is a sought after popular speaker at events around the world. Greg is also author of the books Resilient Storage Network (Elsevier) and The Green and Virtual Data Center (CRC). His blog is at www.storageioblog.com and he can also be found on twitter @storageio.