Create clusters using the job manager
In a flexible management environment, we can submit the Create cluster job. A cluster is a set of servers managed together to balance workload. The job creates a cluster that runs on a deployment manager node. The cluster becomes a managed resource of the job manager.
Start the job manager, the deployment manager, and the federated node to which we want to add a cluster.
If the deployment manager is not a managed node of the job manager, register the deployment manager with the job manager. Registering enables the job manager to manage the deployment manager and its federated nodes. To submit the Create cluster job, a deployment manager node must be a managed node of the job manager.
Determine how we want to configure the cluster:
- Review topics on clusters and workload management, especially the information about setting cluster weights.
- Determine whether we want a cluster to group application servers, proxy servers, or on-demand routers.
- Determine the node to which to add the first cluster member. The target node must be a managed node of the job manager.
- For a cluster of servers that spans multiple systems in a Sysplex and has stateful session beans with an activation policy of Transaction deployed in them, define the passivation directory on a hierarchical file system (HFS) shared across the multiple systems in the Sysplex.
Your ID at the job manager must be authorized for the administrator role or the operator role to submit jobs. When submitting a job, we can specify a user name and password for authentication and authorization at the target or targets. When submitting a job to multiple targets, the user name and password or the credentials for the submitter must apply to all the job targets.
A cluster enables us to manage a group of application servers as a single unit, and distribute client requests among the application servers that are members of the cluster. We might want to create a cluster if we need to:
- Balance the client requests across multiple application servers.
- Provide a highly available environment for the applications.
Use the administrative console of the job manager or the deployment manager to create a cluster on one or more managed nodes. From the console, choose the Create cluster job, specify job options, review the summary, and submit the job. This topic describes how to use the job manager console or the deployment manager console to submit the job.
Instead of using a console, we can run the createCluster job script in the AdministrativeJobs command group. See the Administrative job types topic.
- Click Jobs > Submit from the navigation tree of the administrative console.
- Choose a job to create a cluster.
- Select the Create cluster job type from the list.
- Optionally specify a description of the job.
- Click Next.
- Choose the job targets on which to add the cluster.
Select one or more deployment manager managed nodes to which we can add clusters.
- Select a group of targets from the list, or select Target names.
- If we selected Target names, then specify a target name and click Add, or click Find and specify the chosen targets on the Find targets page.
- If user authentication is required, specify a user name, password, or any other authentication values as needed.
- Click Next.
- Specify parameters for the create cluster job.
- For Cluster name, specify a cluster name that is unique on the targets.
To see the names of existing clusters on the targets, click Jobs > Target resources. The Target resources page lists the clusters, servers, and applications on managed targets. After you determine what cluster names are already used, return to the Specify job parameters page and specify a unique name for the cluster to create.
For example, suppose a managed deployment manager node, myNode01, has one cluster, cluster1. Specify a name that is unique to myNode01: cluster2
- If we do not want to enable node-scoped routing optimization for the cluster, deselect Prefer local (false). The default value is selected (true).
When enabled, node-scoped routing optimization routes requests to the target on which the cluster resides.
- For Cluster type, specify the type of server cluster to create.
To create a cluster to group application servers, leave the field empty. The default type is APPLICATION_SERVER.
Otherwise, specify PROXY_SERVER or ONDEMAND_ROUTER.
- If we are creating a cluster on a z/OS target, optionally specify a cluster short name.
If we do not specify a value, the product generates a unique short name.
- Optionally, expand Additional job parameters and specify values that further define the cluster.
Parameter name Description Create domain To create a replication domain with a name set to the name of the new cluster, select Create domain (true). The product uses the replication domain for HTTP session data replication. The default value is clear (false). Server node To convert an existing server to the first member of the cluster, specify the name of a managed node that has the existing server. Server name To convert an existing server to the first member of the cluster, specify the name of the existing server that resides on the node specified for Server node. Member weight If we want the new cluster member to have a weight value other than 2, the default, specify a different weight value. A valid value is a number between 0 and 100. The weight controls the amount of work directed to a server. If the weight is greater than the weight assigned to other cluster members, the server receives a larger share of the workload. Node group To have all cluster member to belong to a node group, specify the name of the node group. Replication entry If Create domain is selected, optionally specify true to create a replicator entry for this member in the cluster replication domain. The default value is false.
- Click Next.
- Schedule the job.
The times and dates specified are relative to the job manager.
- Optionally specify one or more email addresses where notifications are sent when the job finishes.
If we specify multiple email addresses, separate them with commas.
- Select when the job is available for submission.
- Select the job expiration.
- Optionally specify a recurring interval for the job, a start date and time for the interval, and an end date and time for the interval.
- Click Next.
- Review the summary, and click Finish to submit the job.
The targets run the job and attempt to create a cluster.
What to do next
On the Job status page, click the ID of the create cluster job and view the job status. Click the status refresh icon to refresh the displayed status.
If the job is not successful, view any error messages that result from running the job, correct the error condition, and submit the job again.
If the job is successful, click Jobs > Target resources to see the new cluster in the list of resources. The status of the cluster is Stopped.
After creating the cluster, we can run a job that creates a cluster member. We cannot start the cluster unless it has at least one cluster member.
Clusters and workload management Create clusters Start and stop the job manager Start and stop the deployment manager Start and stop a node Set up a job manager environment Create cluster members using the job manager Administrative job types Find targets Find target resources Target resources collection Create a cluster: Basic cluster settings Create a cluster: Create additional cluster members