18.3.2 Flow of the node switching process in the mutual node switching system

This subsection describes the operations and the flow of processes during the node switching in mutual node switching systems.

Organization of this subsection

(1) Node switching operations
(2) Flow of the node switching process

(1) Node switching operations

The node switching is performed in the mutual node switching system, as shown in the following figure. The following figure shows an example when a failure occurs in the active node virtual host of the executing node 1 (standby node 2) and the node is switched to the spare node virtual host of the standby node 1 (executing node 2):

Figure 18‒2: Node switching operations in the mutual node switching system

To Page Top

(2) Flow of the node switching process

The node switching methods that can be applied in the mutual node switching system are the automatic node switching and the planned node switching. The automatic node switching is a method in which the cluster software automatically switches the node. An automatic node switching occurs, when a failure occurs in the executing node. On the other hand, the planned node switching is a method in which the operator switches the nodes in a planned manner during the node maintenance. The node is switched using the cluster software commands from the executing node.

The following points separately describe the flow of the node switching process for automatic node switching and for planned node switching:

(a) Flow of automatic node switching process

The following figure shows the flow of automatic node switching process in a mutual node switching system. The figure shows the process flow when a failure occurs in the active node virtual host of the executing node 1 (standby node 2) and the node is switched to the spare node virtual host of the standby node 1 (executing node 2):

Figure 18‒3: Flow of automatic node switching process in the mutual node switching system

(b) Flow of planned node switching process

The following figure shows the flow of planned node switching process in the mutual node switching system. The figure shows the process flow when the cluster software commands are used for switching the active node virtual host of the executing node 1 (standby node 2) to the spare node virtual host and the spare node virtual host of the standby node 1 (executing node 2) to the active node virtual host:

Figure 18‒4: Flow of planned node switching process in the mutual node switching system

To Page Top