US Patent 9871712 Health checking in a distributed load balancer

A health check method for a distributed load balancer in which a router receives packets from at least one client and routes packet flows to multiple load balancer (LB) nodes, which in turn distribute the packet flows among multiple server nodes. Each LB node may be responsible for health checking one or more other LB nodes. In addition, each LB node may health check one or more of the server nodes. Heartbeat information for the nodes may be disseminated among the LB nodes according to a gossip protocol. The LB nodes may send LB node membership information to the server nodes. Failure of a node may be detected by the LB nodes according to the heartbeat information, and appropriate actions taken.