The cluster administrator can set up a new cluster by using System Setup. After the cluster is created, the cluster administrator can display the cluster status and attributes, rename the cluster, or assign epsilon to another node in the cluster.
What a cluster is
A cluster consists of one or more nodes grouped together as (HA pairs) to form a scalable cluster. Creating a cluster enables the nodes to pool their resources and distribute work across the cluster, while presenting administrators with a single entity to manage. Clustering also enables continuous service to end users if individual nodes go offline.
Considerations for single-node clusters A single-node cluster is a special implementation of a cluster running on a stand-alone node. You can deploy a single-node cluster if your workload only requires a single node, but does not need nondisruptive operations.
What the cluster management server is
The cluster management server, also called an adminSVM, is a specialized Storage Virtual Machine (SVM) implementation that presents the cluster as a single manageable entity. In addition to serving as the highest-level administrative domain, the cluster management server owns resources that do not logically belong with a data SVM.
Understanding quorum and epsilon
Quorum and epsilon are important measures of cluster health and function that together indicate how clusters address potential communications and connectivity challenges.
Displaying information about the nodes in a cluster
You can display node names, whether the nodes are healthy, and whether they are eligible to participate in the cluster. At the advanced privilege level, you can also display whether a node holds epsilon.
Reassigning epsilon to another node in the cluster
Only one node in the cluster can hold epsilon. Epsilon gives the holding node an extra fractional voting weight in the quorum. You need to reassign epsilon only in rare situations, for example, when you take over an epsilon-holding node in an HA pair for planned maintenance. If you are unsure about whether you need to reassign epsilon, you should contact technical support.
Displaying the status of cluster replication rings
You can display the status of cluster replication rings to help you diagnose cluster-wide problems. If your cluster is experiencing problems, support personnel might ask you to perform this task to assist with troubleshooting efforts.