From 616bcc40f727d0c589dd2ba8aa8337285663eae1 Mon Sep 17 00:00:00 2001
From: Dhia Ayachi <dhia@hashicorp.com>
Date: Wed, 24 Nov 2021 15:46:25 -0500
Subject: [PATCH 1/3] finish the leave process if broadcasting leave timeout

---
 serf/serf.go | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/serf/serf.go b/serf/serf.go
index f214a58d4..53c697878 100644
--- a/serf/serf.go
+++ b/serf/serf.go
@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"encoding/base64"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"io/ioutil"
 	"log"
@@ -727,7 +726,7 @@ func (s *Serf) Leave() error {
 		select {
 		case <-notifyCh:
 		case <-time.After(s.config.BroadcastTimeout):
-			return errors.New("timeout while waiting for graceful leave")
+			s.logger.Printf("[WARN] serf: timeout while waiting for graceful leave")
 		}
 	}
 

From d59a77e01fc935132eb7dc829b747e9140456215 Mon Sep 17 00:00:00 2001
From: Dhia Ayachi <dhia@hashicorp.com>
Date: Mon, 10 Jan 2022 09:10:37 -0500
Subject: [PATCH 2/3] Log broadcast timeout as WARN and finish the Leave
 process.

---
 serf/serf.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/serf/serf.go b/serf/serf.go
index 53c697878..7d8c278d6 100644
--- a/serf/serf.go
+++ b/serf/serf.go
@@ -684,6 +684,7 @@ func (s *Serf) broadcastJoin(ltime LamportTime) error {
 
 // Leave gracefully exits the cluster. It is safe to call this multiple
 // times.
+// If the Leave broadcast timeout, Leave() will try to finish the sequence as best effort.
 func (s *Serf) Leave() error {
 	// Check the current state
 	s.stateLock.Lock()
@@ -733,7 +734,7 @@ func (s *Serf) Leave() error {
 	// Attempt the memberlist leave
 	err := s.memberlist.Leave(s.config.BroadcastTimeout)
 	if err != nil {
-		return err
+		s.logger.Printf("[WARN] serf: timeout waiting for leave broadcast: %s", err.Error())
 	}
 
 	// Wait for the leave to propagate through the cluster. The broadcast

From 3f940397b03a5db67bd87175a15689e8f799766f Mon Sep 17 00:00:00 2001
From: Dhia Ayachi <dhia@hashicorp.com>
Date: Wed, 12 Jan 2022 16:30:31 -0500
Subject: [PATCH 3/3] increase timeout

---
 serf/coalesce_member_test.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/serf/coalesce_member_test.go b/serf/coalesce_member_test.go
index ee4a2a698..ec395bfdf 100644
--- a/serf/coalesce_member_test.go
+++ b/serf/coalesce_member_test.go
@@ -134,7 +134,7 @@ func TestMemberEventCoalesce_TagUpdate(t *testing.T) {
 		Members: []Member{Member{Name: "foo", Tags: map[string]string{"role": "foo"}}},
 	}
 
-	time.Sleep(10 * time.Millisecond)
+	time.Sleep(30 * time.Millisecond)
 
 	select {
 	case e := <-outCh: