Cluster Node A
Node A
HBA 1
Private Network
Node A
HBA 2
Node B
HBA 2
Cluster Node B
Node B
HBA 1
SAN Switch
SAN Switch
Storage Area Network
Cluster
Quorum
Mirrorset
LUN 1
Data RAID set
Node A
LUN 2
Data RAID set
Node B
LUN 3
+
+
+
+
+++++++++++++++++++++++++++++++++++++++++++++++++++
+
+
+
+
+
+
+
+
Figure 91 Storage server cluster diagram
Cluster terms and components
Nodes
The most basic parts of a cluster are the servers, referred to as nodes. A server node is any individual
computer in a cluster or a member of the cluster.
Resources
Hardware and software components that are managed by the cluster service are called cluster resources.
Cluster resources have three defining characteristics:
•
They can be brought online and taken offline.
•
They can be managed in a cluster.
•
They can be owned by only one node at a time.
Examples of cluster resources are IP addresses, network names, physical disk resources, and file shares.
Virtual servers
A virtual server is a cluster group that consists of a static IP Address resource and a Network Name
resource. Several virtual servers can be created. By assigning ownership of the virtual servers to the
different server nodes, the processing load on the storage servers can be distributed between the nodes
of a cluster.
172
Cluster Administration