SMB3 PowerShell changes in Windows Server 2012 R2: Scale-Out Rebalancing (per-share redirection)

Introduction 

Windows Server 2012 R2 introduced a new version of SMB. Technically it’s SMB version 3.02, but we continue to call it just SMB3. The main changes are described at https://technet.microsoft.com/en-us/library/hh831474.aspx.

With this new release, we made a few changes in SMB PowerShell to support the new scenarios and features. This includes a few new cmdlets and some changes to existing cmdlets, with extra care not break any of your existing scripts.

This blog post outlines one of the 7 set of changes related to SMB PowerShell in Windows Server 2012 R2.

 

Scale-Out Rebalancing (per-share redirection)

 

Per-share redirection is the new default behavior for the new SMB Clients (Windows 8.1 or Windows Server 2012 R2), when connecting to a Scale-Out clusters that use a storage system that does not support Direct I/O from all nodes, if running Windows Server 2012 R2. The common scenario here is a Scale-Out File Server backed by Mirrored Storage Spaces.

 

Here are the changes in SMB PowerShell to support SMB Scale-Out per-share redirection:

  • New “Redirected” Boolean property to Get-SmbConnection to indicate that per-share redirection is being used.

  • Get-SmbWitnessClient now includes a “ShareName” property, since witness can track connections per share, not only per server.

  • Get-SmbWitnessClient now includes a “Flags” property, which will show “Share” when doing per-share redirection

 

Notes

 

1) For more details of the new rebalancing behavior of Windows Server 2012 R2, see https://blogs.technet.com/b/josebda/archive/2013/10/30/automatic-smb-scale-out-rebalancing-in-windows-server-2012-r2.aspx

2) This blog post is an updated version of the September 2013 post at  https://blogs.technet.com/b/josebda/archive/2013/09/03/what-s-new-in-smb-powershell-in-windows-server-2012-r2.aspx focused on a single topic.