Best Practices for CSV defrag in Hyper-V (Windows Server 2008R2)
28. 三月 2011 04:33
One of the most significant features in Windows 2008R2 (for Hyper-V)
is Cluster Shared Volumes (CSV) for virtual disks (vhd). This allows NTFS to
behave similar to a clustered file system, addressing many limitations found in
Hyper-V storage with the original release (Windows 2008).
There are three online modes/states for CSV:
- Direct Access: In this state, the CSV is available to all nodes in the cluster (i.e. all your VMs) for direct high performance storage access. This is the state you want in production.
- Redirected Access: In this state, the CSV is still available to all nodes in the cluster, but all I/O is redirected through a single "coordinator" node. Redirected access is used in planned situations where you need to perform certain disk actions that can't have multiple nodes accessing and locking files concurrently, such as a VSS backup or defrag. Channeling all I/O through a coordinator slows I/O and is more likely to cause bottlenecks for production demands.
- Maintenance mode: enabling this mode is a safe means to get to a state where processes that require exclusive access to a volume can be used, such as a maintenance routine like chkdsk.
參考的中文文件：(有圖)
