US Patent 10129180 Transit logical switch within logical router

Some embodiments provide a method for handling failure at one of several peer centralized components of a logical router. At a first one of the peer centralized components of the logical router, the method detects that a second one of the peer centralized components has failed. In response to the detection, the method automatically identifies a network layer address of the failed second peer. The method assumes responsibility for data traffic to the failed peer by broadcasting a message on a logical switch that connects all of the peer centralized components and a distributed component of the logical router. The message instructs recipients to associate the identified network layer address with a data link layer address of the first peer centralized component.