B. This allows the network load to be handled by both devices simultaneously. If only one cluster group
exists, it can only be owned by one node and the other node would not serve any network traffic.
Cluster resource overview
Hardware and software components that are managed by the cluster service are called cluster resources.
Resources represent individual system components. These resources are then organized into groups and
managed as a group.
Some resources are created automatically by the system and other resources must be set up manually.
Resource types:
•
IP Address resource
•
Cluster name resource
•
Cluster Quorum disk resource
•
Physical Disk resource
•
Virtual server name resources
•
CIFS file share resources
•
NFS file share resources
File share resource planning issues
CIFS and NFS are cluster aware protocols that support the Active/Active cluster model, allowing resources
to be distributed and processed on both nodes at the same time. For example, some NFS file share
resources can be assigned to a group owned by a virtual server for NodeA and additional NFS file share
resources can be assigned to a group owned by a virtual server for NodeB.
Configuring the file shares as cluster resources provides for high availability of file shares. Because the
resources are placed into groups, ownership of the files can easily move from one node to the other,
as circumstances require. If the cluster node owning the group of file shares should be shut down or
fail, the other node in the cluster will begin sharing the directories until the original owner node is
brought back on line. At that time, ownership of the group and its resources can be brought back
to the original owner node.
Resource planning
1.
Create at least one virtual server for each node in the cluster.
A virtual server is a resource group consisting of an IP Address resource and a Network Name
resource. Ownership of these virtual servers should be assigned to the different server nodes. In
addition to providing load balancing capabilities, the virtual server allows for the transition of
group resources in failover situations.
2.
Create a virtual server group for each node in the cluster.
Cluster resource groups are used to balance the processing load on the servers. Distribute ownership
of the groups between the virtual servers.
3.
For NFS environments, configure the NFS server.
NFS specific procedures include entering audit and file lock information as well as setting up client
groups and user name mappings. These procedures are not unique to a clustered deployment and
are detailed in the "Microsoft Services for NFS" chapter. Changes to NFS setup information are
automatically replicated to all nodes in a cluster.
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Cluster Administration