2.2.3 Planning Network Connections

You must have at least one public network connection to a local area network and exactly two private interconnects between the cluster nodes. Refer to Chapter 1, Understanding the Sun Cluster Environment, for overviews of Sun Cluster network configurations, and to Appendix A, Configuration Worksheets and Examples, for network planning worksheets.

2.2.3.1 Public Network Connections

Consider these points when planning your public network configuration:

• You must have at least one public network that is attached to all cluster nodes. You can have as many additional public network connections as your hardware configuration allows.

• In configurations providing HA data services, you must provide IP addresses and network interface names for each logical host on each public network. This can lead to many host names. Refer to "2.2.2 Establishing Names and Naming Conventions", for more information. You must add the logical host names to the /etc/hosts files on all cluster nodes.

• Sun Cluster includes a Public Network Management (PNM) component, which enables a public network interface to fail over to another interface within a designated backup group. Refer to the chapter on administering network interfaces in the Sun Cluster 2.2 System Administration Guide for more information about PNM.

2.2.3.2 Private Network Connections

Sun Cluster requires two private networks for normal operation. You must decide whether to use 100 Mbit/sec Ethernet or 1 Gbit/sec Scalable Coherent Interface (SCI) connections for the private networks.

In two-node configurations, these networks may be implemented with point-to-point cables between the cluster nodes. In three- or four-node configurations, they are implemented using hubs or switches. Only private traffic between Sun Cluster nodes is transported on these networks.

If you connect nodes by using SCI switches, each node must be connected to the same port number on both switches. During the installation, note that the port numbers on the switches correspond to node numbers. For example, node 0 is the host physically connect to port 0 on the switch, and so on.

A class C network number (204.152.64) is reserved for private network use by the Sun Cluster nodes. The same network number is used by all Sun Cluster systems.

2.2.3.3 Terminal Concentrator and Administrative Workstation Network Connections

The Terminal Concentrator and administrative workstation connect to a public network with access to the Sun Cluster nodes. You must assign IP addresses and host names for them to enable access to the cluster nodes over the public network.

E10000 systems use a System Service Processor (SSP) instead of a Terminal Concentrator. You will need to assign the SSP a host name, IP address, and root password. You will also need to create a user named "ssp" on the SSP and provide a password for user "ssp" during Sun Cluster installation.