| There are some general configuration options for your NCS environment of which you should be aware. All of these configuration options are available from the Cluster Options page in iManager, shown in Figure 9.3. Figure 9.3. Cluster Options page in iManager. 
To access the Cluster Options page in iManager, perform the following steps: 1. | From within iManager, select the Cluster Options link, found under the Clusters category.
| 2. | In the right pane, use the Object Selector or Object Browser tools to locate your cluster object. After you select the cluster object, the current page will automatically reload.
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From this page, configuration parameters used to configure the entire cluster environment can be accessed. To view these options, select the Properties button from the Cluster Options page. This will open the Cluster Properties page, shown in Figure 9.4. The various configuration settings available from this page are described next. Figure 9.4. Cluster Properties page in iManager. 
IP Address/Port You can view and change the IP address and port assigned to the Cluster object when you installed NCS. The Cluster IP address normally does not need to be changed, but can be if needed. The default cluster port number is 7023, and is automatically assigned when the cluster is created. The cluster port number should not be changed unless there is a TCP port conflict with another resource using the same port. If there is a conflict, you can change the port number to any other value that doesn't cause a conflict. Quorum Triggers The Quorum Triggers configuration is used to define two trigger values that are used during the startup of the cluster. Timeout Timeout specifies the amount of time to wait for the number of servers defined in the Membership field to be up and running. If the timeout period elapses before the quorum membership reaches its specified number, resources will automatically start loading on the servers that are currently up and running in the cluster. Number of Nodes This represents the number of nodes in the quorum that must be running in the cluster before resources will start to load. When you first bring up servers in your cluster, NCS reads the number specified in the Number of Nodes field and waits until that number of servers is up and running in the cluster before it starts loading resources. Set the number to a value greater than 1 so that all resources don't automatically load on the first server that is brought up in the cluster.
Notification NCS can automatically send out email messages for certain cluster events such as cluster and resource state changes or nodes joining or leaving the cluster. Enable Cluster Notification Events Check this box to enable cluster email notifications. If this is not checked, all remaining fields are grayed out. Email Addresses Specify the email address that should receive notifications in the field provided. Repeat this process for each address you want on the notification list. You can provide up to eight email addresses. Receive Only Critical Events Select this radio button if you want administrators to receive notification of only critical events like a node failure or a resource going comatose. Verbose Messages Select this radio button if you want administrators to receive notification of all cluster state changes, including critical events, resource state changes, and nodes joining and leaving the cluster. XML Messages Check this box if you want administrators to receive notifications in XML format. XML messages can be interpreted and formatted in a way that lets you customize the message information for your specific needs.
NOTE NCS uses Postfix for sending email alerts. If you are also running cluster resources that use SMTP, the port configured for Postfix must be changed to avoid port conflicts between the two services. You can modify the port used by Postfix by editing the /etc/postfix/main.cf file. For more information on performing this change, refer to http://www.postfix.org.
Priorities The Priorities page allows you to control the order in which multiple resources start on a given node when the cluster is brought up, or during a failover or failback. For example, if a node fails and two resources fail over to another node, the resource priority will determine which resource loads first. This is useful for ensuring that the most critical resources load first and are available to users before less critical resources. To adjust the priority of a resource, select the resource in the priority list. After selecting the resource, use the up and down arrow buttons to move the resource to a higher or lower priority. Click Apply when finished. Protocols You can use the Protocol link to view or edit the transmit frequency and tolerance settings for all nodes in the cluster, including the master node. Heartbeat Specifies the amount of time between transmits for all nodes in the cluster except the master. For example, if you set this value to 1, nonmaster nodes in the cluster will send a signal that they are alive to the master node every second. Tolerance Specifies the amount of time the master node gives all other nodes in the cluster to signal that they are alive. For example, setting this value to 4 means that if the master node does not receive an "I'm alive" signal from a node in the cluster within four seconds, that node will be removed from the cluster. Master Watchdog Specifies the amount of time between transmits for the master node in the cluster. For example, if you set this value to 1, the master node in the cluster will transmit an "I'm alive" signal to all the other nodes in the cluster every second. Slave Watchdog Specifies the amount of time the master node has to signal that it is alive. For example, setting this value to 5 means that if the nonmaster nodes in the cluster do not receive an "I'm alive" signal from the master within five seconds, the master node will be removed from the cluster and one of the other nodes will become the master node. Maximum Retransmits This option is not currently used with Novell Cluster Services but will be used for future versions.
The master node is generally the first node brought online in the cluster, but if that node fails, any of the other nodes in the cluster can become the master. Cluster Node Properties In addition to editing the configuration of the entire cluster, it is also possible to adjust the IP address of an individual cluster node. This can also be accomplished using the Cluster Options page in iManager. To adjust this setting for an individual node, complete the following steps: 1. | From within iManager, select the Cluster Options link, found under the Clusters category.
| 2. | In the right pane, use the Object Selector or Object Browser tools to locate your cluster object. After you select the cluster object, the current page will automatically reload.
| 3. | In the Cluster Objects list, locate and select the check box for the desired cluster node. When the node has been marked, select Properties in the header of the Cluster Objects window.
| 4. | The IP address for the selected node is the only item that can be adjusted here. Make any necessary changes, and select OK to save your changes and exit back to Cluster Options page.
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From the main Cluster Options page, it is also possible to delete a node from the cluster. To delete a cluster node, select the check box beside the cluster node and click Delete in the header of the Cluster Object window. After a node is deleted, you must unload and reload NCS on each server in the cluster in order for the node deletion to take effect. To do this, run rcnovell-ncs restart from the console of each server in the cluster. |
