Method doProxyElection

ais/vote.go:186–242

(vr *VoteRecord)

}

func (p *proxy) doProxyElection(vr *VoteRecord) {
	var (
		err        error
		curPrimary = vr.Smap.Primary
		timeout    = cmn.Timeout.CplaneOperation() / 2
	)
	// 1. ping current primary (not using apc.QparamAskPrimary as it might be transitioning)
	for i := 0; i < 2; i++ {
		if i > 0 {
			runtime.Gosched()
		}
		smap := p.owner.smap.get()
		if smap.version() > vr.Smap.version() {
			glog.Warningf("%s: %s updated from %s, moving back to idle", p, smap, vr.Smap)
			return
		}
		_, _, err = p.Health(curPrimary, timeout, nil /*ask primary*/)
		if err == nil {
			break
		}
		timeout = cmn.Timeout.CplaneOperation()
	}
	if err == nil {
		// move back to idle
		query := url.Values{apc.QparamAskPrimary: []string{"true"}}
		_, _, err = p.Health(curPrimary, timeout, query /*ask primary*/)
		if err == nil {
			glog.Infof("%s: current primary %s is up, moving back to idle", p, curPrimary)
		} else {
			glog.Errorf("%s: current primary(?) %s responds but does not consider itself primary",
				p.si, curPrimary)
		}
		return
	}
	glog.Infof("%s: primary %s is confirmed down: %v", p, curPrimary, err)

	// 2. election phase 1
	glog.Info("Moving to election state phase 1 (prepare)")
	elected, votingErrors := p.electAmongProxies(vr)
	if !elected {
		glog.Errorf("Election phase 1 (prepare) failed: primary remains %s, moving back to idle", curPrimary)
		return
	}

	// 3. election phase 2
	glog.Info("Moving to election state phase 2 (commit)")
	confirmationErrors := p.confirmElectionVictory(vr)
	for sid := range confirmationErrors {
		if !votingErrors.Contains(sid) {
			glog.Errorf("Error confirming the election: %s was healthy when voting", sid)
		}
	}

	// 4. become!
	glog.Infof("%s: moving (self) to primary state", p.si)
	p.becomeNewPrimary(vr.Primary /*proxyIDToRemove*/)
}