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3.6. Configuring Cluster Members

Configuring cluster members consists of initially configuring nodes in a newly configured cluster, adding members, and deleting members. The following sections provide procedures for initial configuration of nodes, adding nodes, and deleting nodes:

3.6.1. Initially Configuring Members

Creating a cluster consists of selecting a set of nodes (or members) to be part of the cluster. Once you have completed the initial step of creating a cluster and creating fence devices, you need to configure cluster nodes. To initially configure cluster nodes after creating a new cluster, follow the steps in this section. The starting point of the procedure is at the cluster-specific page that you navigate to from Choose a cluster to administer displayed on the cluster tab.
  1. At the detailed menu for the cluster (below the clusters menu), click Nodes. Clicking Nodes causes the display of an Add a Node element and a Configure element with a list of the nodes already configured in the cluster.
  2. Click a link for a node at either the list in the center of the page or in the list in the detailed menu under the clusters menu. Clicking a link for a node causes a page to be displayed for that link showing how that node is configured.
  3. At the bottom of the page, under Main Fencing Method, click Add a fence device to this level.
  4. Select a fence device and provide parameters for the fence device (for example port number).

    Note

    You can choose from an existing fence device or create a new fence device.
  5. Click Update main fence properties and wait for the change to take effect.

3.6.2. Adding a Member to a Running Cluster

To add a member to a running cluster, follow the steps in this section. The starting point of the procedure is at the cluster-specific page that you navigate to from Choose a cluster to administer displayed on the cluster tab.
  1. At the detailed menu for the cluster (below the clusters menu), click Nodes. Clicking Nodes causes the display of an Add a Node element and a Configure element with a list of the nodes already configured in the cluster. (In addition, a list of the cluster nodes is displayed in the center of the page.)
  2. Click Add a Node. Clicking Add a Node causes the display of the Add a node to cluster name page.
  3. At that page, enter the node name in the Node Hostname text box; enter the root password in the Root Password text box. Check the Enable Shared Storage Support checkbox if clustered storage is required. If you want to add more nodes, click Add another entry and enter node name and password for the each additional node.
  4. Click Submit. Clicking Submit causes the following actions:
    1. Cluster software packages to be downloaded onto the added node.
    2. Cluster software to be installed (or verification that the appropriate software packages are installed) onto the added node.
    3. Cluster configuration file to be updated and propagated to each node in the cluster — including the added node.
    4. Joining the added node to cluster.
    A progress page shows the progress of those actions for each added node.
  5. When the process of adding a node is complete, a page is displayed providing a configuration interface for the cluster.
  6. At the detailed menu for the cluster (below the clusters menu), click Nodes. Clicking Nodes causes the following displays:
    • A list of cluster nodes in the center of the page
    • The Add a Node element and the Configure element with a list of the nodes configured in the cluster at the detailed menu for the cluster (below the clusters menu)
  7. Click the link for an added node at either the list in the center of the page or in the list in the detailed menu under the clusters menu. Clicking the link for the added node causes a page to be displayed for that link showing how that node is configured.
  8. At the bottom of the page, under Main Fencing Method, click Add a fence device to this level.
  9. Select a fence device and provide parameters for the fence device (for example port number).

    Note

    You can choose from an existing fence device or create a new fence device.
  10. Click Update main fence properties and wait for the change to take effect.

3.6.3. Deleting a Member from a Cluster

To delete a member from an existing cluster that is currently in operation, follow the steps in this section. The starting point of the procedure is at the Choose a cluster to administer page (displayed on the cluster tab).
  1. Click the link of the node to be deleted. Clicking the link of the node to be deleted causes a page to be displayed for that link showing how that node is configured.

    Note

    To allow services running on a node to fail over when the node is deleted, skip the next step.
  2. Disable or relocate each service that is running on the node to be deleted:

    Note

    Repeat this step for each service that needs to be disabled or started on another node.
    1. Under Services on this Node, click the link for a service. Clicking that link cause a configuration page for that service to be displayed.
    2. On that page, at the Choose a taskdrop-down box, choose to either disable the service are start it on another node and click Go.
    3. Upon confirmation that the service has been disabled or started on another node, click the cluster tab. Clicking the cluster tab causes the Choose a cluster to administer page to be displayed.
    4. At the Choose a cluster to administer page, click the link of the node to be deleted. Clicking the link of the node to be deleted causes a page to be displayed for that link showing how that node is configured.
  3. On that page, at the Choose a taskdrop-down box, choose Delete this node and click Go. When the node is deleted, a page is displayed that lists the nodes in the cluster. Check the list to make sure that the node has been deleted.