Creating a cluster: Create additional cluster members

Use this page to create additional members for a cluster. You can add a member to a cluster when you create the cluster or after you create the cluster. A copy of the first cluster member that you create is stored as part of the cluster data and becomes the template for all additional cluster members that you create.

To add members to a cluster, in the administrative console, click Servers > Clusters > WebSphere application server clusters > cluster_name > Cluster members > New. After you enter the required information about the new cluster member, click Add Member to add this member to the cluster member list.

After adding a cluster member, you might need to change one or more of the property settings for this cluster member, or another cluster member that you just added. To change one or more property settings for any cluster member that you just added, other than the first cluster member, select that cluster member, and then click Edit. When you finish changing the property settings, click Update Member to save your changes.

If you decide not to create a particular cluster member, select the member and then click Delete.

You cannot edit or delete the first cluster member or an already existing cluster member.

If you create additional cluster members immediately after you create the first cluster member, the list of cluster members includes a checklist in front of the names of these additional cluster members. However, a check box does not appear in front of the name of the first cluster member because you cannot delete this member or edit its settings. To modify the first cluster member, click Previous.

Similarly, if you are adding cluster members to a cluster that already has existing members, the existing members appear in the list of cluster members but a check box does not appear in front of the names of these cluster members. To delete one of these existing members or to change the settings of one of these cluster members, in the administrative console click Servers > Clusters > WebSphere application server clusters > cluster_name > Cluster members, and then select the member that you want to delete or whose configuration settings you want to change.

Member name

Specifies the name of the application server that is created for the cluster.

The member name must be unique on the selected node.

Select node

Specifies the node on which the application server resides.

[AIX Solaris HP-UX Linux Windows]In a mixed cell environment, you can use any server from within the node group to create a new cluster member. For example, if the node group to which the cluster belongs consists of a Version 7.0 node and a Version 6.1 node, you can use a server from either the Version 7.0 node or the Version 6.1 node to create a new cluster member.

[z/OS]

Short name

Specifies the short name for this cluster member. This field only displays if you are running on z/OS®.

The short name is the default z/OS job name and identifies the cluster member to the native facilities of the operating system, such as Workload Manager (WLM), Automatic Restart Manager, SAF (for example, RACF®), started task control, and others.

If you specify a short name for a cluster member, the name:
  • Must be one to eight characters in length. By default, the product assumes that you are using a 7-character server short name (JOBNAME). If your naming standards require 8 characters, you can lengthen the 7-character server short name to 8 characters.
  • Must contain only uppercase alphanumeric characters
  • Cannot start with a number
  • Must be unique in the cell
  • Cannot be the same as the value specified on the ClusterTransitionName custom property of any non-clustered server. Do not specify a cluster transition name for a server that is part of a cluster.

If you do not specify a short name, the system assigns a default short name that is automatically unique within the cell. You can change the generated short name to conform with your naming conventions.

Weight

Specifies the amount of work that is directed to the application server.

If the weight value for the server is greater than the weight values that are assigned to other servers in the cluster, the server receives a larger share of the cluster workload. The value can range from 0 to 20. Enter zero to indicate that you do not want requests to route to this application server unless this server is the only server that is available to receive requests.

[z/OS]On z/OS, weight is used to balance some of the workload types, but others are balanced by the z/OS system.
  • For HTTP requests, weights are used to distribute HTTP traffic between the web server plug-in and the controller handling the clustered application server. Assign a higher weight value to the application server that should receive the HTTP traffic.
  • For web services calls, information is transferred from a servant in one application server to a controller in another application server. The application server that receives the call has the highest weight value.
  • Weight has no affect on Internet Inter-ORB Protocol (IIOP) requests. IIOP requests are distributed to the correct application server using the sysplex distributor.

Generate unique HTTP ports

Specifies that a unique HTTP port is generated for the application server. By generating unique HTTP ports for the application server, you avoid potential port collisions and configurations that are not valid.