SMB3.0 provides many enhancements for improved performance, resiliency and security, including:
- SMB Scale-Out: transparently redirect SMB client connections to a different file server cluster node.
- SMB Direct (SMB over RDMA): enables direct memory-to-memory data transfers between servers, with minimal CPU utilization and low latency, using standard RDMA-capable network adapters (iWARP, InfiniBand, and RoCE). Any application which accesses files over SMB can transparently benefit from SMB Direct.
- SMB Multichannel – takes advantage of multiple network interfaces to provide both high performance through bandwidth aggregation, and network fault tolerance through the use of multiple network paths to data on an SMB share. Fast data transfers and network fault tolerance.
- Transparent Failover and node fault tolerance – Supporting business critical server application workloads requires the connection to the storage back end to be continuously available. The new SMB server and client cooperate to make failover of file server cluster nodes transparent to applications, for all file operations, and for both planned cluster resource moves and unplanned node failures.
- Secure data transfer with SMB encryption – protects data in-transit from eavesdropping and tampering attacks. Encrypting File System (EFS) is still required to protect data at rest though.
You can enable cluster disk as new Cluster Shared Volume (CSV). CSV enables all cluster nodes to "own" a "shared" volume at the same time i.e. Active-Active configuration. When CSV 1.0 was first introduced in W2K8 R2, it was only meant for Hyper-V storage to support Live Migration. Match the new CSV 2.0 storage with SMB3.0, it provides a real solid NAS-based alternative to SAN for performance and resiliency at a better value known as Scale-Out File Server (SOFS). Meanwhile, Microsoft is working with hardware partners to create a cluster-in-a-box (CiB) architecture if you prefer appliance-based SOFS solution.
Having singing much praises to SOFS, do note that it is still not meant for every situation. Microsoft recommends that SOFS should not be used if your workload generates a high number of metadata operations, such as opening files, closing files, creating new files, or renaming existing files, which is typical for end-user file shares. Microsoft publishes the following chart to help you to decide when to use traditional file share and SOFS (taken from "When to use Scale-Out File Server"):
If you're already running 10Gigabit Ethernet or higher in your data center, you should further optimise your existing investment and leverage on the full performance benefits of SMB Direct (i.e. SMB over RDMA). Do note that the servers should have Network Interface Cards (NICs) that support RDMA (iWARP or RoCE). Here is a link on RDMA enabled NICs that support Windows Server 2012.