Server availability is a higher priority than ever. The demands of a
“24x7” global marketplace mean downtime can equate to lost customers, revenue,
and productivity.
Windows Server 2008 brought many new or enhanced configuration,
management, and diagnostic features to failover clustering that made setting up
and managing the clusters easier for IT staff. Windows Server 2008 R2 builds on
that work with improvements aimed at enhancing the validation process for new
or existing clusters, simplifying the management of clustered virtual machines
(which run with Hyper-V), providing a Windows PowerShell interface, and
providing more options for migrating settings from one cluster to another. These
enhancements combine to provide you with a near turn-key solution for making
applications and services highly available.
Cluster
Validation Tool
By using the Cluster Validation Tool, you can perform tests to
determine whether your system, storage, and network configuration is suitable
for a cluster. The Cluster Validation Tool verifies that the nodes meet all of
the operating system requirements, that the networks are configured correctly,
that there are at least two separate networks on each node for redundancy, and
that the storage subsystem supports clustering.
Cluster
Setup
Once validated by the Cluster Validation Tool, the installation has
been streamlined so that administrators can set up a cluster in just a few
clicks. The cluster installation is completely scriptable, enabling
administrators to automate cluster deployments.
Cluster
Migration
When migrating a clustered service setting can be captured and copied to
another cluster. This reduces the time it takes to build the new cluster and
configure the services. Administrators can migrate cluster workloads currently
running on Windows Server 2003 and Windows Server 2008 to Windows Server 2008
R2. The migration process supports every workload currently supported on
Windows Server 2003 and Windows Server 2008.
Cluster
Management and Operations
The cluster management interface has been optimized to make managing the
cluster easier and more intuitive. Cluster management can be performed from the
command line as well as the Windows Management Instrumentation (WMI) management
console.
Cluster
Backup and Restore
Full integration with the Volume Shadow Copy Service makes it easier to
back up and restore cluster configurations.
Cluster
Infrastructure
With Windows Server 2008 R2, you can configure a cluster so that the
quorum resource, which contains the cluster configuration settings, is not a
single point of failure.
Cluster
Storage
Administrators have better control and can achieve better
performance with storage than was possible in previous releases. Failover
clusters now support GUID partition table (GPT) disks that can have capacities
of larger than 2 terabytes, for increased disk size and robustness.
Administrators can now modify resource dependencies while resources are online,
which means they can make an additional disk available without interrupting
access to the application that will use it. And administrators can run tools in
Maintenance Mode to check, fix, back up, or restore disks more easily and with
less disruption to the cluster.
Cluster
Network
Networking has been enhanced to support Internet Protocol version 6
(IPv6) as well as Domain Name System (DNS) for name resolution, removing the
requirement to have WINS and NetBIOS name broadcasts. Other network
improvements include managing dependencies between network names and IP
addresses: If either of the IP addresses associated with a network name is
available, the network name will remain available. Because of the architecture
of Cluster Shared Volumes (CSV), there is improved cluster node connectivity
fault tolerance that directly affects Virtual Machines running on the cluster.
The CSV architecture implements a mechanism, known as dynamic I/O redirection,
in which I/O can be rerouted within the failover cluster based on connection
availability.
Cluster
Security
Internet Protocol security (IPsec) can be used between clients and the
cluster nodes, as well as between nodes so that you can authenticate and
encrypt the data. Access to the cluster can also be audited to determine who
connected to the cluster and when.
Benefits
Windows Server Failover Clustering is an important feature of the Windows
Server platform that can help improve your server availability. When one server
fails, another server begins to provide service in its place. This process is
called failover. Failover clusters in Windows Server 2008 R2 provide you with
seamless easy-to-deploy high availability for important databases, messaging
servers, file and print services, and virtualized workloads.
With failover clustering you can help build redundancy into your network
and eliminate single points of failure. The improvements to failover clustering
in Windows Server 2008 R2 are aimed at simplifying clusters, making them more
secure, and enhancing cluster stability.
