Abstract: A method of upgrading controller cluster includes the following steps. A leader controller downloads an upgrade file of a latest version from a version server and executes upgrade in version. The leader controller sends an upgrade announcement message to region controllers and receive upgrade announcement response messages having the same type of product and different current version information from the region controllers. The leader controller records the corresponding region controllers included in the upgrade announcement response messages, sends a download start message to the recorded region controllers, and starts a local file server for the recorded region controllers.

Abstract: A method of upgrading controller cluster includes the following steps. A leader controller downloads an upgrade file of a latest version from a version server and executs upgrade in version. The leader controller sends an upgrade announcement message to region controllers and receive upgrade announcement response messages having the same type of product and different current version information from the region controllers. The leader controller records the corresponding region controllers included in the upgrade announcement response messages, sends a download start message to the recorded region controllers, and starts a local file server for the recorded region controllers.

Abstract: Link Aggregation Control Protocol (LACP) loop detection in a network that includes a Software Defined Networking (SDN) controller, a server and an edge switch is provided. The server virtualizes a virtual switch and virtual machines. The virtual switch includes uplink ports that are aggregated with downlink ports of the edge switch to form an aggregation group, and the SDN controller controls operation of the virtual switch. The virtual switch periodically sends a LACP data unit (LACPDU) message to the edge switch via each of the uplink ports in the aggregation group. The virtual switch receives a LACPDU message from the edge switch via one of the uplink ports in the aggregation group. When it is determined that the received LACPDU message originates from the virtual switch itself, the virtual switch keeping one of the uplink ports running and shutting down the rest of the uplink ports.