Abstract: A method (400, 500, 600, 700) for synchronizing state information in a security gateway cluster comprising at least two nodes comprises the following steps. Synchronizing (403) state information by sending state information from a first node of said at least two nodes, detecting (401) in said security gateway cluster a predetermined irregularly occurring action, and initiating (402) synchronization of state information as a response to said action. The state information is sent to at least a second node of said at least two nodes. Corresponding computer program, computer program product, software entities (910, 920), a node (900) of a security gateway cluster (950) and a security gateway cluster are also presented.