IPMP and Dynamic Reconfiguration

The dynamic reconfiguration (DR) feature of Oracle Solaris enables you to reconfigure system hardware, such as interfaces, while the system is running. DR can be used only on systems that support this feature. On systems that support DR, IPMP is integrated into the Reconfiguration Coordination Manager (RCM) framework. Thus, you can safely attach, detach, or reattach NICs and RCM manages the dynamic reconfiguration of system components. For example, you can attach, plumb, and then add new interfaces to existing IPMP groups. After these interfaces have been configured, they are immediately available for use by IPMP.

All requests to detach NICs are first checked to ensure that connectivity can be preserved. For example, by default you cannot detach a NIC that is not in an IPMP group. You also cannot detach a NIC that contains the only functioning interfaces in an IPMP group. However, if you must remove the system component, you can override this behavior by using the -f option of the cfgadm command, as explained in the cfgadm(1M) man page.

If the checks are successful, the in.mpathd daemon sets the OFFLINE flag for the interface. All test addresses on the interfaces are unconfigured. Then, the NIC is unplumbed from the system. If any of these steps fail, or if the DR of other hardware on the same system component fails, then the previous configuration is restored to its original state. A status message about this event is displayed. Otherwise, the detach request completes successfully. You can remove the component from the system. No existing connections are disrupted.