Manage clusters

This topic contains information that covers some of the tasks that involve managing your clusters.

If you have not considered the type of interface you are going to use to manage your clusters, see Solutions for managing clusters before going any further.

Some of the changes that you can make to the cluster once you have configured it include the following:

• Add a node to a cluster
  You can add a node to a cluster using iSeries™ Navigator or commands.
• Start a cluster node
  Starting a cluster node starts cluster resource services on a node in the cluster. Beginning with cluster version 3, a node can start itself and will be able to rejoin the current active cluster, provided it can find an active node in the cluster.
• End a cluster node
  Stopping or ending a node stops cluster resource services on that node.
• Adjust the cluster version of a cluster
  The cluster version defines the level at which all the nodes in the cluster are actively communicating with each other.
• Delete a cluster
  When you delete a cluster, cluster resource services will be ended on all active cluster nodes and they will be removed from the cluster.
• Create a CRG
  You can create several types of CRGs: application, data, device and peer CRGs.
• Start a CRG
  You can start several types of CRGs: application, data, device and peer CRGs.
• Change the recovery domain for a cluster resource group
  You can change the roles of nodes in a recovery domain for a cluster resource group, as well as add or remove nodes from a recovery domain. For a device cluster resource group, you can also change site name and data port IP addresses for a node in the recovery domain.
• Perform a switchover
  Performing a manual switchover causes the current primary node to switch over to the backup node, as defined in the cluster resource group's recovery domain.
• Add a node to a device domain
  A device domain is a subset of nodes in a cluster that share device resources.
• Remove a node from a device domain
  A device domain is a subset of nodes in a cluster that share device resources.
• How a system event affects a cluster
  Certain commands that end system functions, such as Power Down System (PWRDWNSYS), End System (ENDSYS), and End Subsystem (ENDSBS) commands may end a cluster abruptly, causing a cluster partition to occur.
• Create a cluster administrative domain
  A cluster administrative domain can be created within iSeries™ Navigator or with the Create Cluster Administrative Domain (CRTADMDMN) command.
• Add monitored resource entries
  You can add a monitored resource entry to a cluster administrative domain that represents a resource that is shared among nodes.
• Monitor a cluster administrative domain
  Once a cluster administrative domain is created and the appropriate monitored resource entries are added, the cluster administrator should monitor the activity within the administrative domain to insure that the monitored resources remain consistent.
• Monitor cluster status
  Taking appropriate actions when necessary, the cluster resource services performs basic monitoring of a cluster and its components using the reliable message function and heartbeat monitoring.
• Cluster performance
  When changes are made to a cluster, the overhead necessary to manage the cluster can be affected.
• End cluster jobs
  Never try to end a cluster job directly.
• Resource Monitoring and Control (RMC)
  Resource Monitoring and Control (RMC) is a generalized framework for managing, monitoring, and manipulating resources such as physical or logical system entities.
• Job structure and user queues
  When managing cluster, you need to know about job structures and user queues.
• Maintain user profiles on all nodes
  You can use two mechanisms for maintaining user profiles on all nodes within a cluster.
• Backup and recovery of clusters
  If you use clustering on your systems, it is still important that you create a backup and recovery strategy to protect your data.
• Save cluster configurations
  You can use commands to save your cluster resource group objects.