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3.1.1.7 Cluster Networks and Cluster Network Interfaces

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A cluster network represents a communication path between cluster nodes. A cluster network interface represents a connection on a node for a particular cluster network. There is at most one cluster network interface for a given node and cluster network combination.

A cluster network is uniquely identified in a cluster by separate Unicode strings that contain the name and ID of the cluster network. Both the network name and network ID are case-insensitive and can contain any Unicode character in any position except as follows: the string is null-terminated, the string contains no Unicode null character other than for termination, and the string contains at least one character that is not Unicode 0x20 and null. In addition to these exceptions, the network ID string does not include the backslash character ('\'). The size of network name and ID strings are not limited by this protocol. The network name can be changed as long as the name remains unique among all cluster networks. The network ID is assigned by the cluster when the cluster network is added to the cluster and remains constant until the cluster network is deleted. A cluster network cannot have a name that is the same as the ID of a cluster network.

A cluster network interface is uniquely identified in a cluster by separate Unicode strings that contain the name and ID of the cluster network interface. Both the network interface name and network interface ID are case-insensitive and can contain any Unicode character in any position except as follows: the string is null-terminated, the string contains no Unicode null character other than for termination, and the string contains at least one character that is not Unicode null. In addition to these exceptions, the network interface ID string does not include the backslash character ("\"). The network interface name is created by the cluster and set through implementation-specific methods and protocols between servers. The network interface name is case-insensitive and can change as long as the name remains unique among all cluster network interfaces. The network interface ID is assigned by the cluster when the cluster network interface is added to the cluster and remains constant until the cluster network interface is deleted. A cluster network interface cannot have a name that is the same as the ID of a cluster network interface.

A cluster network has a role in the cluster as either private, public, mixed, or none. A private cluster network carries internal cluster communication, a public cluster network provides clients with access to cluster applications, and a cluster network that is mixed carries both internal communication and client-based communication. A cluster network with a role of "none" does not carry any cluster or client related communication. Mixed and private cluster networks are referred to as a cluster internal network. The role of each cluster network is stored in the nonvolatile configuration data in the cluster state.

Cluster Networks and cluster network interfaces are added to and removed from the nonvolatile cluster state through implementation-specific methods and protocols between servers.

ClusAPI Protocol version 2.0 servers normally maintain a cluster internal network prioritization list. The cluster internal network prioritization list includes each cluster internal network and indicates the order the server will choose a cluster network for internal cluster communications. The cluster internal network prioritization list is part of the nonvolatile cluster state. A server typically maintains the cluster internal network prioritization list as an array of cluster network IDs in decreasing priority order, as specified for the NetworkIdList parameter for ApiSetNetworkPriorityOrder (section 3.1.4.1.87). When an internal network is added to the nonvolatile cluster state, its position in the cluster internal network prioritization list is arbitrary and implementation-specific. When a cluster network is removed from the nonvolatile cluster state, it is removed from the cluster internal network prioritization list. Any ordering of cluster networks by version 3.0 servers is implementation-specific.

Cluster network and cluster network interface objects have no defined characteristics.

The nonvolatile cluster state associated with a cluster network and cluster network interface includes a set of flags; these flags can be set by a client individually for each cluster network and cluster network interface, and the server returns them when queried by a client, but those flags will not be interpreted by the server and will not be associated with any semantics on the server.

A ClusAPI Protocol client can perform the following management operations on a cluster network:

A ClusAPI Protocol client can perform the following management operations on a cluster network interface:

Get State: Return the current state of the designated cluster network interface. For more information, see section 3.1.4.1.94 (ClusAPI Protocol version 2.0) and section 3.1.4.2.94 (ClusAPI Protocol version 3.0).

Query configuration: Query the configuration data for a cluster network interface. For more information, see sections 3.1.4.1.95 through 3.1.4.1.98 (protocol version 2), and sections 3.1.4.2.95 through 3.1.4.2.98 (protocol version 3).

Set configuration: Change the configuration data for a cluster network interface. For more information, see sections 3.1.4.1.88 and 3.1.4.1.89 (protocol version 2), and sections 3.1.4.2.88 and 3.1.4.2.89 (protocol version3).