Method gratuitousARP

engine/core.go:333–362

gratuitousARP sends gratuitous ARP messages at regular intervals, if this node is the HA master.

()

// gratuitousARP sends gratuitous ARP messages at regular intervals, if this
// node is the HA master.
func (e *Engine) gratuitousARP() {
	arpTicker := time.NewTicker(e.config.GratuitousARPInterval)
	var announced bool
	for {
		select {
		case <-arpTicker.C:
			if e.haManager.state() != spb.HaState_LEADER {
				if announced {
					log.Info("Stopping gratuitous ARPs")
					announced = false
				}
				continue
			}
			if !announced {
				log.Infof("Starting gratuitous ARPs every %s", e.config.GratuitousARPInterval)
				announced = true
			}
			e.arpLock.Lock()
			arpMap := e.arpMap
			e.arpLock.Unlock()
			if err := e.ncc.ARPSendGratuitous(arpMap); err != nil {
				log.Fatalf("Failed to send gratuitous ARP: %v", err)
			}

		case <-e.shutdownARP:
			e.shutdownARP <- true
			return
		}
	}
}

// manager is responsible for managing and co-ordinating various parts of the
// seesaw engine.