diff --git a/strategy.go b/strategy.go
index 6c2efdc..2852dcc 100644
--- a/strategy.go
+++ b/strategy.go
@@ -10,24 +10,26 @@ import (
 )
 
 // NewStrategyDialer returns a new Strategy Dialer
-func NewStrategyDialer(strategy string, dialers []Dialer, website string, duration int) Dialer {
-	var dialer Dialer
+func NewStrategyDialer(strategy string, dialers []Dialer, website string, interval int) Dialer {
 	if len(dialers) == 0 {
-		dialer = Direct
-	} else if len(dialers) == 1 {
+		return Direct
+	}
+
+	if len(dialers) == 1 {
+		return dialers[0]
+	}
+
+	var dialer Dialer
+	switch strategy {
+	case "rr":
+		dialer = newRRDialer(dialers, website, interval)
+		logf("forward to remote servers in round robin mode.")
+	case "ha":
+		dialer = newHADialer(dialers, website, interval)
+		logf("forward to remote servers in high availability mode.")
+	default:
+		logf("not supported forward mode '%s', just use the first forward server.", conf.Strategy)
 		dialer = dialers[0]
-	} else if len(dialers) > 1 {
-		switch strategy {
-		case "rr":
-			dialer = newRRDialer(dialers, website, duration)
-			logf("forward to remote servers in round robin mode.")
-		case "ha":
-			dialer = newHADialer(dialers, website, duration)
-			logf("forward to remote servers in high availability mode.")
-		default:
-			logf("not supported forward mode '%s', just use the first forward server.", conf.Strategy)
-			dialer = dialers[0]
-		}
 	}
 
 	return dialer
@@ -42,15 +44,15 @@ type rrDialer struct {
 
 	// for checking
 	website  string
-	duration int
+	interval int
 }
 
 // newRRDialer returns a new rrDialer
-func newRRDialer(dialers []Dialer, website string, duration int) *rrDialer {
+func newRRDialer(dialers []Dialer, website string, interval int) *rrDialer {
 	rr := &rrDialer{dialers: dialers}
 
 	rr.website = website
-	rr.duration = duration
+	rr.interval = interval
 
 	for k := range dialers {
 		rr.status.Store(k, true)
@@ -104,7 +106,7 @@ func (rr *rrDialer) checkDialer(idx int) {
 	d := rr.dialers[idx]
 
 	for {
-		time.Sleep(time.Duration(rr.duration) * time.Second * time.Duration(retry>>1))
+		time.Sleep(time.Duration(rr.interval) * time.Second * time.Duration(retry>>1))
 		retry <<= 1
 
 		if retry > 16 {
@@ -154,7 +156,6 @@ func (ha *haDialer) Dial(network, addr string) (net.Conn, error) {
 	d := ha.dialers[ha.idx]
 
 	result, ok := ha.status.Load(ha.idx)
-
 	if ok && !result.(bool) {
 		d = ha.NextDialer(addr)
 	}