An IPMP configuration typically consists of two or more physical interfaces on the same system that are attached to the same LAN.
These interfaces can belong to an IPMP group in either of the following configurations:
Active-active configuration – An IPMP group in which all underlying interfaces are active. An active interface is an IP interface that is currently available for use by the IPMP group.
Active-standby configuration – An IPMP group in which at least one interface is administratively configured as a standby interface. Although idle, the standby interface is monitored by the multipathing daemon to track the interface's availability, depending on how the interface is configured. If link-failure notification is supported by the interface, link-based failure detection is used. If the interface is configured with a test address, probe-based failure detection is also used. If an active interface fails, the standby interface is automatically deployed as needed. You can configure as many standby interfaces as are needed for an IPMP group.
You can also configure a single interface can in its own IPMP group. The single-interface IPMP group behaves the same as an IPMP group with multiple interfaces. However, this IPMP configuration does not provide high availability for network traffic. If the underlying interface fails, then the system loses all capability to send or receive traffic. The purpose of configuring a single-interface IPMP group is to monitor the availability of the interface by using failure detection. By configuring a test address on the interface, the multipathing daemon can track the interface by using probe-based failure detection.
Typically, a single-interface IPMP group configuration is used with other technologies that have broader failover capabilities, such as the Oracle Solaris Cluster software. The system can continue to monitor the status of the underlying interface, but the Oracle Solaris Cluster software provides the functionality to ensure availability of the network when a failure occurs. For more information about the Oracle Solaris Cluster software, see Oracle Solaris Cluster Concepts Guide .
An IPMP group without underlying interfaces can also exist, such as a group whose underlying interfaces have been removed. The IPMP group is not destroyed, but the group cannot be used to send and receive traffic. As underlying interfaces are brought online for the group, then the data addresses of the IPMP interface are allocated to these interfaces, and the system resumes hosting network traffic.