diff --git a/app/router/router.go b/app/router/router.go
index 569dba67b..d0cc1d999 100644
--- a/app/router/router.go
+++ b/app/router/router.go
@@ -15,7 +15,7 @@ import (
 
 // Router is an implementation of routing.Router.
 type Router struct {
-	domainStrategy Config_DomainStrategy
+	domainStrategy DomainStrategy
 	rules          []*Rule
 	balancers      map[string]*Balancer
 	dns            dns.Client
@@ -86,7 +86,7 @@ func (r *Router) pickRouteInternal(ctx routing.Context) (*Rule, routing.Context,
 	// this prevents cycle resolving dead loop
 	skipDNSResolve := ctx.GetSkipDNSResolve()
 
-	if r.domainStrategy == Config_IpOnDemand && !skipDNSResolve {
+	if r.domainStrategy == DomainStrategy_IpOnDemand && !skipDNSResolve {
 		ctx = routing_dns.ContextWithDNSClient(ctx, r.dns)
 	}
 
@@ -96,7 +96,7 @@ func (r *Router) pickRouteInternal(ctx routing.Context) (*Rule, routing.Context,
 		}
 	}
 
-	if r.domainStrategy != Config_IpIfNonMatch || len(ctx.GetTargetDomain()) == 0 || skipDNSResolve {
+	if r.domainStrategy != DomainStrategy_IpIfNonMatch || len(ctx.GetTargetDomain()) == 0 || skipDNSResolve {
 		return nil, ctx, common.ErrNoClue
 	}