6. Virtual Fibre Channel
Existing technologies often present obstacles when considering the
migration of your server workloads into the cloud. An example of this
might be if you have an AlwaysOn failover cluster instance running on
SQL Server 2012 that’s configured to use a Fibre Channel SAN for high performance.
You’d like to migrate this workload into the cloud, but Hyper-V in
Windows Server 2008 R2 does not support directly connecting to Fibre
Channel from within VMs. As a result, you’ve postponed performing such
a migration because you want to protect your existing investment in
expensive Fibre Channel technology.
Virtual Fibre Channel removes this blocking issue by providing Fibre Channel ports within the guest
operating system of VMs on Hyper-V hosts running Windows Server 2012.
This now allows a server application like SQL Server running within the
guest operation system of a VM to connect directly to LUNs on a Fibre
Channel SAN.
Implementing this kind of solution requires that the drivers for
your HBAs support Virtual Fibre Channel. Some HBAs from Brocade and
QLogic already include such updated drivers, and more vendors are
expected to follow. Virtual Fibre Channel also requires that you
connect only to LUNs, and you can’t use a LUN as boot media for your VMs.
Virtual Fibre Channel also provides the benefits of allowing you to
use any advanced storage functionality of your existing SAN directly
from your VMs. You can even use it to cluster guest operating systems over Fibre Channel to provide high availability for VMs.
Note that VMs must use Windows Server 2008, Windows Server 2008 R2,
or Windows Server 2012 as the guest operating system if they are
configured with a virtual Fibre Channel adapter.
7. SMB 3
Windows Server 2012 introduces SMB 3, version 3 of the Server
Message Block (SMB) protocol to provide powerful new features for
continuously available file servers. SMB is a network file sharing
protocol that allows applications to read and write to files and to
request services from services over a network. (Note that some
documentation on TechNet and MSDN still refer to this version as SMB 3.)
The improvements in SMB 3 are designed to provide increased performance,
reliability, and availability in scenarios where data is stored on file
shares. Some of the new features and enhancements in SMB 3 include:
-
SMB Direct
Enables using
network adapters capable of Remote Direct Memory Access (RDMA) such as
iWARP, Infiniband, or RoCE (RDMA over Converged Ethernet) that can
function at full speed and low latency with very little processor
overhead on the host. When such adapters are used on Hyper-V hosts, you
can store VM files on a remote file server and achieve performance
similar to if the files were stored locally on the host.
SMB Direct makes possible a new class of file servers for enterprise
environments, and the new File Server role in Windows Server 2012
demonstrates these capabilities in full. Such file servers experience
minimal processor utilization for file storage processing and the
ability to use high-speed RDMA-capable NICs including iWARP,
InfiniBand, and RoCE. They can provide remote storage solutions
equivalent in performance to Fibre Channel, but at a lower cost. They
can use converged network fabrics in datacenters and are easy to
provision, manage, and migrate.
-
SMB Directory Leasing
Reduces round-trips
from client to server because metadata is retrieved from a longer
living directory cache. Cache coherency is maintained as clients are
notified when directory information changes on the server. The result
of using SMB Directory Leasing can be improved application response
times, especially in in branch office scenarios.
-
SMB Encryption
Enables end-to-end
encryption of SMB data to protect network traffic from eavesdropping
when travelling over untrusted networks. SMB Encryption can be
configured either on a per-share basis or for the entire file server.
It adds no cost overhead and removes the need for configuring IPsec and
using specialized encryption hardware and WAN accelerators.
-
SMB Multichannel
Allows aggregation of network bandwidth
and network fault tolerance when multiple paths become available
between the SMB client and the SMB server. The benefit of this that it
allows server applications to take full advantage of all available
network bandwidth. The result is that your server applications become
more resilient to network failure.
SMB Multichannel configures itself automatically by detecting and
using multiple network paths when they become available. It can use NIC
teaming failover but doesn’t require such capability to work. Possible
scenarios can include:
-
Single NIC, but using Receive-Side Scaling (RSS) enables more processors to process the network traffic
-
Multiple NICs with NIC Teaming, which allows SMB to use a single IP address per team
-
Multiple NICs without NIC Teaming, where each NIC must have a unique IP address and is required for RDMA-capable NICs
-
SMB Scale Out
Allows you to
create file shares that provide simultaneous access to data files with
direct I/O through all the nodes in your file server cluster. The result is improved use of network bandwidth and load balancing of the file server clients, and also optimization of performance for server applications. SMB Scale Out requires using CSV version 2, which is included in Windows Server 2012, and lets you seamlessly increase available bandwidth by adding cluster nodes.
-
SMB Transparent Failover
Allows
administrators to perform hardware or software maintenance of nodes in
a clustered file server without interruption to server applications
storing their data on file shares. If a hardware or software failure
happens on a cluster node, SMB clients will reconnect transparently to
another cluster node with no interruption for server applications
storing data on these shares.
SMB Transparent
Failover supports both planned failovers (such as maintenance
operations) and unplanned failovers (for example, due to hardware
failure). Implementing this feature requires the use of failover
clustering, that both the server running the application and the file
server are running Windows Server 2012, and that the file shares on the
file server have been shared for continuous availability.
The implementation of SMB 3 in Windows Server 2012 also includes new SMB performance
counters that can provide detailed, per-share information about
throughput, latency, and I/O per second (IOPS). These counters are
designed for server applications like Hyper-V and SQL Server, which can
store files on remote file shares to enable administrators to analyze
the performance of the file shares where server application data is
stored.