8.3 Configuring Cluster Protocol Properties

You can use the Cluster Protocol property pages to view or edit the transmit frequency and tolerance settings for all nodes in the cluster, including the master node. 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.

IMPORTANT:If you change any protocol properties, you should restart all servers in the cluster to ensure that the changes take effect.

  1. In iManager, select Clusters, then select Cluster Options.

  2. Specify the cluster name, or browse and select the Cluster object.

  3. Click the Properties button under the cluster name.

  4. Click the Protocols tab.

    The Protocols page also lets you view the script used to configure the cluster protocol settings, but not to change it. Changes made to the protocols setting automatically update the scripts.

  5. Specify values for the cluster protocols properties.

    For information, see the following:

  6. Click Apply or OK to save changes.

  7. Restart all nodes in the cluster to make the changes take effect.

8.3.1 Heartbeat

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, non-master nodes in the cluster send a signal that they are alive to the master node every second.

8.3.2 Tolerance

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 is removed from the cluster.

8.3.3 Master Watchdog

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 transmits an “I'm alive” signal to all the other nodes in the cluster every second.

If you are using multipath I/O to manage multiple paths between the server and the shared drive, ensure that you allow sufficient time in the watchdog setting for a path failover to avoid unnecessary cluster resource failovers between nodes. Test the failover time of the MPIO solution you are using, then adjust the watchdog setting upward accordingly.

8.3.4 Slave Watchdog

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 non-master nodes in the cluster do not receive an “I'm alive” signal from the master within five seconds, the master node is removed from the cluster and one of the other nodes becomes the master node.

If you are using multipath I/O to manage multiple paths between the server and the shared drive, ensure that you allow sufficient time in the watchdog setting for a path failover to avoid unnecessary cluster resource failovers between nodes. Test the failover time of the MPIO solution you are using, then adjust the watchdog setting upward accordingly.

8.3.5 Maximum Retransmits

This value is set by default, and should not be changed.