%3CLINGO-SUB%20id%3D%22lingo-sub-371889%22%20slang%3D%22en-US%22%3EUnderstanding%20the%20state%20of%20your%20Cluster%20Shared%20Volumes%3C%2FLINGO-SUB%3E%3CLINGO-BODY%20id%3D%22lingo-body-371889%22%20slang%3D%22en-US%22%3E%0A%20%26lt%3Bmeta%20http-equiv%3D%22Content-Type%22%20content%3D%22text%2Fhtml%3B%20charset%3DUTF-8%22%20%2F%26gt%3B%3CSTRONG%3EFirst%20published%20on%20MSDN%20on%20Dec%2005%2C%202013%20%3C%2FSTRONG%3E%20%3CBR%20%2F%3E%20Cluster%20Shared%20Volumes%20(CSV)%20is%20the%20clustered%20file%20system%20for%20the%20Microsoft%20Private%20cloud%2C%20first%20introduced%20in%20Windows%20Server%202008%20R2.%20In%20Windows%20Server%202012%2C%20we%20radically%20improved%20the%20CSV%20architecture.%20We%20presented%20a%20deep%20dive%20of%20these%20architecture%20improvements%20at%20%3CA%20href%3D%22https%3A%2F%2Fchannel9.msdn.com%2FEvents%2FTechEd%2FEurope%2F2012%2FWSV430%22%20target%3D%22_blank%22%20rel%3D%22noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%22%3E%20TechEd%202012%20%3C%2FA%3E%20.%20Building%20on%20this%20new%20and%20improved%20architecture%2C%20in%20Windows%20Server%202012%20R2%2C%20we%20have%20introduced%20several%20%3CA%20href%3D%22http%3A%2F%2Ftechnet.microsoft.com%2Fen-us%2Flibrary%2Fdn265972.aspx%22%20target%3D%22_blank%22%20rel%3D%22noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%22%3E%20new%20CSV%20features%20%3C%2FA%3E%20.%20In%20this%20blog%2C%20I%20am%20going%20to%20discuss%20one%20of%20these%20new%20features%20%E2%80%93%20the%20new%20Get-ClusterSharedVolumeState%20Windows%20Server%20Failover%20Clustering%20PowerShell%C2%AE%20cmdlet.%20This%20cmdlet%20enables%20you%20to%20view%20the%20state%20of%20your%20CSV.%20Understanding%20the%20state%20of%20your%20CSV%20is%20useful%20in%20troubleshooting%20failures%20as%20well%20as%20optimizing%20the%20performance%20of%20your%20CSV.%20In%20the%20remainder%20of%20this%20blog%2C%20I%20will%20explain%20how%20to%20use%20this%20cmdlet%20as%20well%20as%20how%20to%20interpret%20the%20information%20provided%20by%20the%20cmdlet.%20%3CBR%20%2F%3E%3CH2%20id%3D%22toc-hId-1679712684%22%20id%3D%22toc-hId-1710247373%22%20id%3D%22toc-hId-1710247373%22%20id%3D%22toc-hId-1710247373%22%20id%3D%22toc-hId-1710247373%22%20id%3D%22toc-hId-1710247373%22%20id%3D%22toc-hId-1710247373%22%20id%3D%22toc-hId-1710247373%22%20id%3D%22toc-hId-1710247373%22%20id%3D%22toc-hId-1710247373%22%3EGet-ClusterSharedVolumeState%20Windows%20PowerShell%C2%AE%20cmdlet%3C%2FH2%3E%3CBR%20%2F%3E%20The%20Get-ClusterSharedVolumeState%20cmdlet%20allows%20you%20to%20view%20the%20state%20of%20your%20CSV%20on%20a%20node%20in%20the%20cluster.%20Note%20that%20the%20state%20of%20your%20CSV%20can%20vary%20between%20the%20nodes%20of%20a%20cluster.%20Therefore%2C%20it%20might%20be%20useful%20to%20determine%20the%20state%20of%20your%20CSV%20on%20multiple%20or%20all%20nodes%20of%20your%20cluster.%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20To%20use%20the%20%3CA%20href%3D%22http%3A%2F%2Ftechnet.microsoft.com%2Fen-us%2Flibrary%2Fdn456528.aspx%22%20target%3D%22_blank%22%20rel%3D%22noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%22%3E%20Get-ClusterSharedVolumeState%20%3C%2FA%3E%20cmdlet%20open%20a%20new%20Windows%20PowerShell%20console%20and%20run%20the%20following%3A%20%3CBR%20%2F%3E%3CUL%3E%3CBR%20%2F%3E%3CLI%3ETo%20view%20the%20state%20of%20all%20CSVs%20on%20all%20the%20nodes%20of%20your%20cluster%3C%2FLI%3E%3CBR%20%2F%3E%3C%2FUL%3E%3CBR%20%2F%3E%20Get-ClusterSharedVolumeState%20%3CBR%20%2F%3E%3CUL%3E%3CBR%20%2F%3E%3CLI%3ETo%20view%20the%20state%20of%20all%20CSVs%20on%20a%20subset%20of%20the%20nodes%20in%20your%20cluster%3C%2FLI%3E%3CBR%20%2F%3E%3C%2FUL%3E%3CBR%20%2F%3E%20Get-ClusterSharedVolumeState%20%E2%80%93Node%20clusternode1%2Cclusternode2%20%3CBR%20%2F%3E%3CUL%3E%3CBR%20%2F%3E%3CLI%3ETo%20view%20the%20state%20of%20a%20subset%20of%20CSVs%20on%20all%20the%20nodes%20of%20your%20cluster%3C%2FLI%3E%3CBR%20%2F%3E%3C%2FUL%3E%3CBR%20%2F%3E%20Get-ClusterSharedVolumeState%20%E2%80%93Name%20%22Cluster%20Disk%202%22%2C%22Cluster%20Disk%203%22%20%3CBR%20%2F%3E%3CP%3EOR%3C%2FP%3E%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20Get-ClusterSharedVolume%20%22Cluster%20Disk%202%22%20%7C%20Get-ClusterSharedVolumeState%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90445i5F0FFBA71525FC80%22%20%2F%3E%20%3CBR%20%2F%3E%3CH2%20id%3D%22toc-hId--872444277%22%20id%3D%22toc-hId--841909588%22%20id%3D%22toc-hId--841909588%22%20id%3D%22toc-hId--841909588%22%20id%3D%22toc-hId--841909588%22%20id%3D%22toc-hId--841909588%22%20id%3D%22toc-hId--841909588%22%20id%3D%22toc-hId--841909588%22%20id%3D%22toc-hId--841909588%22%20id%3D%22toc-hId--841909588%22%3EUnderstanding%20the%20state%20of%20your%20CSV%3C%2FH2%3E%3CBR%20%2F%3E%20The%20Get-ClusterSharedVolumeState%20cmdlet%20output%20provides%20two%20important%20pieces%20of%20information%20for%20a%20particular%20CSV%20%E2%80%93%20the%20state%20of%20the%20CSV%20and%20the%20reason%20why%20the%20CSV%20is%20in%20that%20particular%20state.%20There%20are%20three%20states%20of%20a%20CSV%20%E2%80%93%20Direct%2C%20File%20System%20Redirected%20and%20Block%20Redirected.%20I%20will%20now%20examine%20the%20output%20of%20this%20cmdlet%20for%20each%20of%20these%20states.%20%3CBR%20%2F%3E%3CH2%20id%3D%22toc-hId-870366058%22%20id%3D%22toc-hId-900900747%22%20id%3D%22toc-hId-900900747%22%20id%3D%22toc-hId-900900747%22%20id%3D%22toc-hId-900900747%22%20id%3D%22toc-hId-900900747%22%20id%3D%22toc-hId-900900747%22%20id%3D%22toc-hId-900900747%22%20id%3D%22toc-hId-900900747%22%20id%3D%22toc-hId-900900747%22%3EDirect%20Mode%3C%2FH2%3E%3CBR%20%2F%3E%20In%20Direct%20Mode%2C%20I%2FO%20operations%20from%20the%20application%20on%20the%20cluster%20node%20can%20be%20sent%20directly%20to%20the%20storage.%20It%20therefore%2C%20bypasses%20the%20NTFS%20or%20ReFS%20volume%20stack.%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90446iB7BBB8457FCB7BE1%22%20%2F%3E%20%3CBR%20%2F%3E%3CH2%20id%3D%22toc-hId--1681790903%22%20id%3D%22toc-hId--1651256214%22%20id%3D%22toc-hId--1651256214%22%20id%3D%22toc-hId--1651256214%22%20id%3D%22toc-hId--1651256214%22%20id%3D%22toc-hId--1651256214%22%20id%3D%22toc-hId--1651256214%22%20id%3D%22toc-hId--1651256214%22%20id%3D%22toc-hId--1651256214%22%20id%3D%22toc-hId--1651256214%22%3E%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90447i3C5A4FAD9497E49A%22%20%2F%3E%3C%2FH2%3E%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90448i0039DFB6DCDD279B%22%20%2F%3E%20%3CBR%20%2F%3E%3CH2%20id%3D%22toc-hId-61019432%22%20id%3D%22toc-hId-91554121%22%20id%3D%22toc-hId-91554121%22%20id%3D%22toc-hId-91554121%22%20id%3D%22toc-hId-91554121%22%20id%3D%22toc-hId-91554121%22%20id%3D%22toc-hId-91554121%22%20id%3D%22toc-hId-91554121%22%20id%3D%22toc-hId-91554121%22%20id%3D%22toc-hId-91554121%22%3EFile%20System%20Redirected%20Mode%3C%2FH2%3E%3CBR%20%2F%3E%20In%20File%20System%20Redirected%20mode%2C%20I%2FO%20on%20a%20cluster%20node%20is%20redirected%20at%20the%20top%20of%20the%20CSV%20pseudo-file%20system%20stack%20over%20SMB%20to%20the%20disk.%20This%20traffic%20is%20written%20to%20the%20disk%20via%20the%20NTFS%20or%20ReFS%20file%20system%20stack%20on%20the%20coordinator%20node.%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90449i23148B8ECA5968D9%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90450iFEA565AA047A576E%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90451i102AED84E0D81CC0%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90452i1F662538170564A6%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90453iDB5348023EAA2146%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CSTRONG%3E%20Note%3A%20%3C%2FSTRONG%3E%20%3CBR%20%2F%3E%3CUL%3E%3CBR%20%2F%3E%3CLI%3EWhen%20a%20CSV%20is%20in%20File%20System%20Redirected%20Mode%2C%20I%2FO%20for%20the%20volume%20will%20not%20be%20cached%20in%20the%20%3CA%20href%3D%22http%3A%2F%2Fblogs.msdn.com%2Fb%2Fclustering%2Farchive%2F2012%2F03%2F22%2F10286676.aspx%22%20target%3D%22_blank%22%20rel%3D%22noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%20noopener%20noreferrer%22%3E%20CSV%20Block%20Cache%20%3C%2FA%3E%20.%3C%2FLI%3E%3CBR%20%2F%3E%3CLI%3EData%20deduplication%20occurs%20on%20a%20per%20file%20basis.%20Therefore%2C%20when%20a%20file%20on%20a%20CSV%20volume%20is%20deduped%2C%20all%20I%2FO%20for%20that%20file%20will%20occur%20in%20File%20System%20Redirected%20mode.%20I%2FO%20for%20the%20file%20will%20not%20be%20cached%20in%20the%20CSV%20Block%20Cache%20%E2%80%93%20it%20will%20instead%20be%20cached%20in%20the%20Deduplication%20Cache.%20For%20the%20remaining%20non-deduped%20files%2C%20CSV%20will%20be%20in%20direct%20mode.%20The%20state%20of%20the%20CSV%20will%20be%20reflected%20as%20being%20in%20%3CSTRONG%3E%20Direct%20%3C%2FSTRONG%3E%20mode.%3C%2FLI%3E%3CBR%20%2F%3E%3CLI%3EThe%20Failover%20Cluster%20Manager%20will%20show%20a%20volume%20as%20in%20%3CSTRONG%3E%20Redirected%20Access%20%3C%2FSTRONG%3E%20only%20when%20it%20is%20in%20File%20System%20Redirected%20Mode%20and%20the%20%3CSTRONG%3E%20FileSystemRedirectedIOReason%20%3C%2FSTRONG%3E%20is%20%3CSTRONG%3E%20UserRequest%20%3C%2FSTRONG%3E%20.%3C%2FLI%3E%3CBR%20%2F%3E%3C%2FUL%3E%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90454i3787AF70569147B4%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90455i84A5EEE69B377EBE%22%20%2F%3E%20%3CBR%20%2F%3E%3CH2%20id%3D%22toc-hId-1803829767%22%20id%3D%22toc-hId-1834364456%22%20id%3D%22toc-hId-1834364456%22%20id%3D%22toc-hId-1834364456%22%20id%3D%22toc-hId-1834364456%22%20id%3D%22toc-hId-1834364456%22%20id%3D%22toc-hId-1834364456%22%20id%3D%22toc-hId-1834364456%22%20id%3D%22toc-hId-1834364456%22%20id%3D%22toc-hId-1834364456%22%3EBlock%20Redirected%20Mode%3C%2FH2%3E%3CBR%20%2F%3E%20In%20Block%20level%20redirected%20mode%2C%20I%2FO%20passes%20through%20the%20local%20CSVFS%20proxy%20file%20system%20stack%20and%20is%20written%20directly%20to%20Disk.sys%20on%20the%20coordinator%20node.%20As%20a%20result%20it%20avoids%20traversing%20the%20NTFS%2FReFS%20file%20system%20stack%20twice.%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90456iC49EDD1AE977E635%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90457i3FA5A74E49468ECD%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90458i37318E0CBE86900C%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20%3CIMG%20src%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F90459iACEC922FE952F2F2%22%20%2F%3E%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20In%20conclusion%2C%20the%20Get-ClusterSharedVolumeState%20cmdlet%20is%20a%20powerful%20tool%20that%20enables%20you%20to%20understand%20the%20state%20of%20your%20Cluster%20Shared%20Volume%20and%20thus%20troubleshoot%20failures%20and%20optimize%20the%20performance%20of%20your%20private%20cloud%20storage%20infrastructure.%20%3CBR%20%2F%3E%20%3CBR%20%2F%3E%20Thanks!%20%3CBR%20%2F%3E%20Subhasish%20Bhattacharya%20%3CBR%20%2F%3E%20Senior%20Program%20Manager%20%3CBR%20%2F%3E%20Clustering%20and%20High%20Availability%20%3CBR%20%2F%3E%20Microsoft%3C%2FLINGO-BODY%3E%3CLINGO-TEASER%20id%3D%22lingo-teaser-371889%22%20slang%3D%22en-US%22%3EFirst%20published%20on%20MSDN%20on%20Dec%2005%2C%202013%20Cluster%20Shared%20Volumes%20(CSV)%20is%20the%20clustered%20file%20system%20for%20the%20Microsoft%20Private%20cloud%2C%20first%20introduced%20in%20Windows%20Server%202008%20R2.%3C%2FLINGO-TEASER%3E%3CLINGO-LABS%20id%3D%22lingo-labs-371889%22%20slang%3D%22en-US%22%3E%3CLINGO-LABEL%3Ecluster%20shared%20volumes%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3Ecluster%20troubleshooting%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3Esubhasish%20bhattacharya%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3Ewindows%20server%202012%20r2%3C%2FLINGO-LABEL%3E%3C%2FLINGO-LABS%3E%3CLINGO-SUB%20id%3D%22lingo-sub-1483751%22%20slang%3D%22en-US%22%3ERe%3A%20Understanding%20the%20state%20of%20your%20Cluster%20Shared%20Volumes%3C%2FLINGO-SUB%3E%3CLINGO-BODY%20id%3D%22lingo-body-1483751%22%20slang%3D%22en-US%22%3E%3CP%3EHi%26nbsp%3B%3CA%20href%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fuser%2Fviewprofilepage%2Fuser-id%2F60405%22%20target%3D%22_blank%22%3E%40Rob%20Hindman%3C%2FA%3E%26nbsp%3Bthanks%20for%20your%20article.%26nbsp%3B%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3EThere%20is%20a%20lot%20of%20pro%20and%20cons%20of%20using%20ReFS%20as%20a%20filesystem%20for%20Hyper-V%20machines.%20See%20also%26nbsp%3B%3C%2FP%3E%3CP%3E%3CA%20href%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Ffailover-clustering%2Fcluster-shared-volume-a-systematic-approach-to-finding%2Fbc-p%2F1483528%23M307%22%20target%3D%22_blank%22%20rel%3D%22noopener%22%3Ehttps%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Ffailover-clustering%2Fcluster-shared-volume-a-systematic-approach-to-finding%2Fbc-p%2F1483528%23M307%3C%2FA%3E%26nbsp%3B%2B%20comments%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3E%3CSTRONG%3EWhy%20does%20a%20CSVFS%20preformatted%20with%20ReFS%20prevent%20DirectIO%3F%3C%2FSTRONG%3E%26nbsp%3B-%20state%20Server%202019%201809%2C%20as%20of%20June%202020%3CBR%20%2F%3E%3CBR%20%2F%3EThe%20overall%20other%20benefits%20of%20using%20ReFS%20with%20Hyper-V%20are%20clearly%20documented.%20Not%20alone%20for%20Storage%20Spaces%20Direct.%20Here%20we%20have%20no%20Storage%20Spaces%20involved%20at%20all%2C%20but%20direct%20attached%20SAS%20Frontend%20LUNs%2C%20means%20storage%20is%20directly%20attached%20to%20the%20cluster%20nodes.%3CBR%20%2F%3E%3CBR%20%2F%3E%3CBR%20%2F%3E%3CBR%20%2F%3EAll%20CSVFS%20that%20are%20ReFS%20has%20Stateinfo%20FileSystemRedirected%2C%20If%20I%20create%20a%20CSVFS%20with%20NTFS%2064k%2C%20it%20is%20going%20direct.%26nbsp%3B%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3EExample%3A%3C%2FP%3E%3CP%3ECSV-NTFS%20is%20a%20LUN%20GPT%20preformatted%20with%20NTFS%2064k%20file%20allocation%20size%3CBR%20%2F%3EVM-DATA%20is%20is%20a%20LUN%20GPT%20preformatted%20with%20ReFS%203.4%20(Server%202019)%2064k%20file%20allocation%20size%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3E%3CSPAN%20class%3D%22lia-inline-image-display-wrapper%20lia-image-align-inline%22%20image-alt%3D%22redirectedstate_allCSVFS_ntfs.png%22%20style%3D%22width%3A%20788px%3B%22%3E%3CIMG%20src%3D%22https%3A%2F%2Fgxcuf89792.i.lithium.com%2Ft5%2Fimage%2Fserverpage%2Fimage-id%2F200534iD1193FBB719DA0A4%2Fimage-size%2Flarge%3Fv%3D1.0%26amp%3Bpx%3D999%22%20title%3D%22redirectedstate_allCSVFS_ntfs.png%22%20alt%3D%22redirectedstate_allCSVFS_ntfs.png%22%20%2F%3E%3C%2FSPAN%3E%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3ENowhere%20I%20find%20a%20reason%20for%20this.%20Bug%3F%20Affects%20Server%202019.%26nbsp%3B%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3Ecc%3A%26nbsp%3B-ERR%3AREF-NOT-FOUND-%40Elden%20Christensen%26nbsp%3B%2C%26nbsp%3B-ERR%3AREF-NOT-FOUND-%3CA%20href%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Ffailover-clustering%2Fcluster-shared-volume-diagnostics%2Fba-p%2F371908%22%20target%3D%22_blank%22%3Ehttps%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Ffailover-clustering%2Fcluster-shared-volume-diagnostics%2Fba-p%2F371908%3C%2FA%3E%3C%2FP%3E%3C%2FLINGO-BODY%3E%3CLINGO-SUB%20id%3D%22lingo-sub-1503336%22%20slang%3D%22en-US%22%3ERe%3A%20Understanding%20the%20state%20of%20your%20Cluster%20Shared%20Volumes%3C%2FLINGO-SUB%3E%3CLINGO-BODY%20id%3D%22lingo-body-1503336%22%20slang%3D%22en-US%22%3E%3CP%3E%3CA%20href%3D%22https%3A%2F%2Ftechcommunity.microsoft.com%2Ft5%2Fuser%2Fviewprofilepage%2Fuser-id%2F60405%22%20target%3D%22_blank%22%3E%40Rob%20Hindman%3C%2FA%3E%26nbsp%3Bwhy%20this%20is%20not%20part%20of%20the%20offical%20documentation.%20Marcel%20K%C3%BCppers%20(MVP)%20discussed%20this%20issue%20years%20ago%20on%20Technet%20and%20this%20blogpost.%3C%2FP%3E%3CP%3E%3CA%20href%3D%22https%3A%2F%2Fwww.windowspro.de%2Fmarcel-kueppers%2Frefs-ntfs-vor-nachteile-dateisysteme-server-2016%22%20target%3D%22_blank%22%20rel%3D%22nofollow%20noopener%20noreferrer%20noopener%20noreferrer%22%3Ehttps%3A%2F%2Fwww.windowspro.de%2Fmarcel-kueppers%2Frefs-ntfs-vor-nachteile-dateisysteme-server-2016%3C%2FA%3E%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3C%2FLINGO-BODY%3E
Microsoft
First published on MSDN on Dec 05, 2013
Cluster Shared Volumes (CSV) is the clustered file system for the Microsoft Private cloud, first introduced in Windows Server 2008 R2. In Windows Server 2012, we radically improved the CSV architecture. We presented a deep dive of these architecture improvements at TechEd 2012 . Building on this new and improved architecture, in Windows Server 2012 R2, we have introduced several new CSV features . In this blog, I am going to discuss one of these new features – the new Get-ClusterSharedVolumeState Windows Server Failover Clustering PowerShell® cmdlet. This cmdlet enables you to view the state of your CSV. Understanding the state of your CSV is useful in troubleshooting failures as well as optimizing the performance of your CSV. In the remainder of this blog, I will explain how to use this cmdlet as well as how to interpret the information provided by the cmdlet.

Get-ClusterSharedVolumeState Windows PowerShell® cmdlet


The Get-ClusterSharedVolumeState cmdlet allows you to view the state of your CSV on a node in the cluster. Note that the state of your CSV can vary between the nodes of a cluster. Therefore, it might be useful to determine the state of your CSV on multiple or all nodes of your cluster.

To use the Get-ClusterSharedVolumeState cmdlet open a new Windows PowerShell console and run the following:

  • To view the state of all CSVs on all the nodes of your cluster


Get-ClusterSharedVolumeState

  • To view the state of all CSVs on a subset of the nodes in your cluster


Get-ClusterSharedVolumeState –Node clusternode1,clusternode2

  • To view the state of a subset of CSVs on all the nodes of your cluster


Get-ClusterSharedVolumeState –Name "Cluster Disk 2","Cluster Disk 3"

OR



Get-ClusterSharedVolume "Cluster Disk 2" | Get-ClusterSharedVolumeState

Understanding the state of your CSV


The Get-ClusterSharedVolumeState cmdlet output provides two important pieces of information for a particular CSV – the state of the CSV and the reason why the CSV is in that particular state. There are three states of a CSV – Direct, File System Redirected and Block Redirected. I will now examine the output of this cmdlet for each of these states.

Direct Mode


In Direct Mode, I/O operations from the application on the cluster node can be sent directly to the storage. It therefore, bypasses the NTFS or ReFS volume stack.




File System Redirected Mode


In File System Redirected mode, I/O on a cluster node is redirected at the top of the CSV pseudo-file system stack over SMB to the disk. This traffic is written to the disk via the NTFS or ReFS file system stack on the coordinator node.











Note:

  • When a CSV is in File System Redirected Mode, I/O for the volume will not be cached in the CSV Block Cache .

  • Data deduplication occurs on a per file basis. Therefore, when a file on a CSV volume is deduped, all I/O for that file will occur in File System Redirected mode. I/O for the file will not be cached in the CSV Block Cache – it will instead be cached in the Deduplication Cache. For the remaining non-deduped files, CSV will be in direct mode. The state of the CSV will be reflected as being in Direct mode.

  • The Failover Cluster Manager will show a volume as in Redirected Access only when it is in File System Redirected Mode and the FileSystemRedirectedIOReason is UserRequest .





Block Redirected Mode


In Block level redirected mode, I/O passes through the local CSVFS proxy file system stack and is written directly to Disk.sys on the coordinator node. As a result it avoids traversing the NTFS/ReFS file system stack twice.









In conclusion, the Get-ClusterSharedVolumeState cmdlet is a powerful tool that enables you to understand the state of your Cluster Shared Volume and thus troubleshoot failures and optimize the performance of your private cloud storage infrastructure.

Thanks!
Subhasish Bhattacharya
Senior Program Manager
Clustering and High Availability
Microsoft
2 Comments
Established Member

Hi @Rob Hindman thanks for your article. 

 

There is a lot of pro and cons of using ReFS as a filesystem for Hyper-V machines. See also 

https://techcommunity.microsoft.com/t5/failover-clustering/cluster-shared-volume-a-systematic-approa... + comments

 

Why does a CSVFS preformatted with ReFS prevent DirectIO? - state Server 2019 1809, as of June 2020

The overall other benefits of using ReFS with Hyper-V are clearly documented. Not alone for Storage Spaces Direct. Here we have no Storage Spaces involved at all, but direct attached SAS Frontend LUNs, means storage is directly attached to the cluster nodes.

All CSVFS that are ReFS has Stateinfo FileSystemRedirected, If I create a CSVFS with NTFS 64k, it is going direct. 

 

Example:

CSV-NTFS is a LUN GPT preformatted with NTFS 64k file allocation size
VM-DATA is is a LUN GPT preformatted with ReFS 3.4 (Server 2019) 64k file allocation size

 

redirectedstate_allCSVFS_ntfs.png

 

Nowhere I find a reason for this. Bug? Affects Server 2019. 

 

cc: @Elden Christensen , https://techcommunity.microsoft.com/t5/failover-clustering/cluster-shared-volume-diagnostics/ba-p/37...

Occasional Contributor

@Rob Hindman why this is not part of the offical documentation. Marcel Küppers (MVP) discussed this issue years ago on Technet and this blogpost.

https://www.windowspro.de/marcel-kueppers/refs-ntfs-vor-nachteile-dateisysteme-server-2016