Merge pull request kubernetes#87505 from neolit123/1.18-handle-etcd-members-without-names

kubeadm: improvements to the concurrent etcd member join support

Author: k8s-ci-robot

cmd/kubeadm/app/util/etcd/etcd.go

@@ -42,7 +42,7 @@ const etcdTimeout = 2 * time.Second
 
 // Exponential backoff for etcd operations
 var etcdBackoff = wait.Backoff{
-	Steps:    9,
+	Steps:    11,
 	Duration: 50 * time.Millisecond,
 	Factor:   2.0,
 	Jitter:   0.1,
@@ -128,9 +128,9 @@ func NewFromCluster(client clientset.Interface, certificatesDir string) (*Client
 }
 
 // dialTimeout is the timeout for failing to establish a connection.
-// It is set to 20 seconds as times shorter than that will cause TLS connections to fail
+// It is set to >20 seconds as times shorter than that will cause TLS connections to fail
 // on heavily loaded arm64 CPUs (issue #64649)
-const dialTimeout = 20 * time.Second
+const dialTimeout = 40 * time.Second
 
 // Sync synchronizes client's endpoints with the known endpoints from the etcd membership.
 func (c *Client) Sync() error {
@@ -303,12 +303,20 @@ func (c *Client) AddMember(name string, peerAddrs string) ([]Member, error) {
 	// Returns the updated list of etcd members
 	ret := []Member{}
 	for _, m := range resp.Members {
-		// fixes the entry for the joining member (that doesn't have a name set in the initialCluster returned by etcd)
-		if m.Name == "" {
-			ret = append(ret, Member{Name: name, PeerURL: m.PeerURLs[0]})
-		} else {
-			ret = append(ret, Member{Name: m.Name, PeerURL: m.PeerURLs[0]})
+		// If the peer address matches, this is the member we are adding.
+		// Use the name we passed to the function.
+		if peerAddrs == m.PeerURLs[0] {
+			ret = append(ret, Member{Name: name, PeerURL: peerAddrs})
+			continue
+		}
+		// Otherwise, we are processing other existing etcd members returned by AddMembers.
+		memberName := m.Name
+		// In some cases during concurrent join, some members can end up without a name.
+		// Use the member ID as name for those.
+		if len(memberName) == 0 {
+			memberName = strconv.FormatUint(m.ID, 16)
 		}
+		ret = append(ret, Member{Name: memberName, PeerURL: m.PeerURLs[0]})
 	}
 
 	// Add the new member client address to the list of endpoints