Communications requirements for clusters

Use any type of communications media in your clustering environment as long as it supports Internet Protocol (IP).

Cluster resource services uses TCP/IP and UDP/IP protocols to communicate between nodes. Local area networks (LANs), wide area networks (WANs), OptiConnect system area networks (SANs), or any combination of these connectivity devices are supported. Your choice should be based on the following factors:

• Volume of transactions
• Response time requirements
• Distance between the nodes
• Cost considerations

You can use these same considerations when determining the connection media to be used to connect primary and backup locations of resources. When planning your cluster, it is recommended that you designate one or more of your backup nodes in remote locations in order to survive a site loss disaster.

To avoid performance problems that might be caused by inadequate capacity, you need to evaluate the communication media that is used to handle the volumes of information that are sent from node to node. You can choose which physical media you prefer to use such as token ring, Ethernet, asynchronous transfer mode (ATM), SPD OptiConnect, or Virtual OptiConnect (a high-speed internal connection between logical partitions).