fix: when local dns error occurs try every dns (#1063)

main.go

@@ -136,8 +136,8 @@ func run() {
 		}()
 	}
 
-	// 初始化默认DNS
-	util.InitDefaultDNS(*customDNS, conf.Lang)
+	// 初始化备用DNS
+	util.InitBackupDNS(*customDNS, conf.Lang)
 
 	// 等待网络连接
 	util.WaitInternet(dns.Addresses)

util/net_resolver.go

@@ -8,20 +8,18 @@ import (
 )
 
 // BackupDNS will be used if DNS error occurs.
-var BackupDNS = []string{}
+var BackupDNS = []string{"1.1.1.1", "8.8.8.8", "9.9.9.9", "223.5.5.5"}
 
-func InitDefaultDNS(customDNS, lang string) {
+func InitBackupDNS(customDNS, lang string) {
 	if customDNS != "" {
 		BackupDNS = []string{customDNS}
 		return
 	}
 
 	if lang == language.Chinese.String() {
-		BackupDNS = []string{"223.5.5.5", "114.114.114.114"}
-		return
+		BackupDNS = []string{"223.5.5.5", "114.114.114.114", "119.29.29.29"}
 	}
 
-	BackupDNS = []string{"1.1.1.1", "8.8.8.8"}
 }
 
 // SetDNS sets the dialer.Resolver to use the given DNS server.

util/wait_internet.go

@@ -1,7 +1,6 @@
 package util
 
 import (
-	"math/rand"
 	"strings"
 	"time"
 )
@@ -14,6 +13,7 @@ import (
 //   - https://github.com/ddev/ddev/blob/v1.22.7/pkg/globalconfig/global_config.go#L776
 func WaitInternet(addresses []string) {
 	delay := time.Second * 5
+	retryTimes := 0
 
 	for {
 		for _, addr := range addresses {
@@ -27,10 +27,11 @@ func WaitInternet(addresses []string) {
 			Log("等待网络连接: %s", err)
 			Log("%s 后重试...", delay)
 
-			if isDNSErr(err) && len(BackupDNS) > 0 {
-				dns := BackupDNS[rand.Intn(len(BackupDNS))]
+			if isDNSErr(err) || retryTimes > 0 {
+				dns := BackupDNS[retryTimes%len(BackupDNS)]
 				Log("本机DNS异常! 将默认使用 %s, 可参考文档通过 -dns 自定义 DNS 服务器", dns)
 				SetDNS(dns)
+				retryTimes = retryTimes + 1
 			}
 
 			time.Sleep(delay)