try ping again after no response immediately

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"errors"
 	"flag"
 	"fmt"
 	"github.com/go-ping/ping"
@@ -38,6 +39,7 @@ var (
 	journalLog      = flag.Bool("journal", false, "Log to systemd journal instead of stdout")
 	configFlag      = flag.String("config", "config.yaml", "Set config file to use")
 	reBandwidth     = regexp.MustCompile(`(?m)bandwidth\s(\d+)Mbit`)
+	NoResponseError = errors.New("no response")
 )
 
 type UploadManager struct {
@@ -115,7 +117,7 @@ func doPing(host string, count int, interval time.Duration) (*ping.Statistics, e
 	}
 	log.Debugf("[PING] %s: %s±%s %d%% loss", host, pinger.Statistics().AvgRtt, pinger.Statistics().StdDevRtt, pinger.Statistics().PacketLoss)
 	if pinger.Statistics().PacketLoss == 100 {
-		return nil, fmt.Errorf("no response")
+		return nil, NoResponseError
 	}
 	return pinger.Statistics(), nil
 }
@@ -190,7 +192,9 @@ outerLoop:
 				stats, err = doPing(conf.Host, conf.ConformationPPP, time.Second)
 				if err != nil {
 					log.Warningf("ping to %s failed: %v", conf.Host, err)
+					if !errors.Is(err, NoResponseError) {
 						time.Sleep(time.Duration(conf.Interval) * time.Minute)
+					}
 					continue
 				}