[VOL-5486] Fix deprecated versions

Change-Id: I3e03ea246020547ae75fa92ce8cf5cbba7e8f3bb
Signed-off-by: Abhay Kumar <abhay.kumar@radisys.com>
diff --git a/vendor/go.etcd.io/etcd/server/v3/embed/etcd.go b/vendor/go.etcd.io/etcd/server/v3/embed/etcd.go
new file mode 100644
index 0000000..95c0d6d
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/server/v3/embed/etcd.go
@@ -0,0 +1,952 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package embed
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	defaultLog "log"
+	"math"
+	"net"
+	"net/http"
+	"net/url"
+	"runtime"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/soheilhy/cmux"
+	"go.uber.org/zap"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials/insecure"
+	"google.golang.org/grpc/keepalive"
+
+	"go.etcd.io/etcd/api/v3/version"
+	"go.etcd.io/etcd/client/pkg/v3/transport"
+	"go.etcd.io/etcd/client/pkg/v3/types"
+	"go.etcd.io/etcd/client/v3/credentials"
+	"go.etcd.io/etcd/pkg/v3/debugutil"
+	runtimeutil "go.etcd.io/etcd/pkg/v3/runtime"
+	"go.etcd.io/etcd/server/v3/config"
+	"go.etcd.io/etcd/server/v3/etcdserver"
+	"go.etcd.io/etcd/server/v3/etcdserver/api/etcdhttp"
+	"go.etcd.io/etcd/server/v3/etcdserver/api/rafthttp"
+	"go.etcd.io/etcd/server/v3/features"
+	"go.etcd.io/etcd/server/v3/storage"
+	"go.etcd.io/etcd/server/v3/verify"
+)
+
+const (
+	// internal fd usage includes disk usage and transport usage.
+	// To read/write snapshot, snap pkg needs 1. In normal case, wal pkg needs
+	// at most 2 to read/lock/write WALs. One case that it needs to 2 is to
+	// read all logs after some snapshot index, which locates at the end of
+	// the second last and the head of the last. For purging, it needs to read
+	// directory, so it needs 1. For fd monitor, it needs 1.
+	// For transport, rafthttp builds two long-polling connections and at most
+	// four temporary connections with each member. There are at most 9 members
+	// in a cluster, so it should reserve 96.
+	// For the safety, we set the total reserved number to 150.
+	reservedInternalFDNum = 150
+)
+
+// Etcd contains a running etcd server and its listeners.
+type Etcd struct {
+	Peers   []*peerListener
+	Clients []net.Listener
+	// a map of contexts for the servers that serves client requests.
+	sctxs            map[string]*serveCtx
+	metricsListeners []net.Listener
+
+	tracingExporterShutdown func()
+
+	Server *etcdserver.EtcdServer
+
+	cfg Config
+
+	// closeOnce is to ensure `stopc` is closed only once, no matter
+	// how many times the Close() method is called.
+	closeOnce sync.Once
+	// stopc is used to notify the sub goroutines not to send
+	// any errors to `errc`.
+	stopc chan struct{}
+	// errc is used to receive error from sub goroutines (including
+	// client handler, peer handler and metrics handler). It's closed
+	// after all these sub goroutines exit (checked via `wg`). Writers
+	// should avoid writing after `stopc` is closed by selecting on
+	// reading from `stopc`.
+	errc chan error
+
+	// wg is used to track the lifecycle of all sub goroutines which
+	// need to send error back to the `errc`.
+	wg sync.WaitGroup
+}
+
+type peerListener struct {
+	net.Listener
+	serve func() error
+	close func(context.Context) error
+}
+
+// StartEtcd launches the etcd server and HTTP handlers for client/server communication.
+// The returned Etcd.Server is not guaranteed to have joined the cluster. Wait
+// on the Etcd.Server.ReadyNotify() channel to know when it completes and is ready for use.
+func StartEtcd(inCfg *Config) (e *Etcd, err error) {
+	if err = inCfg.Validate(); err != nil {
+		return nil, err
+	}
+	serving := false
+	e = &Etcd{cfg: *inCfg, stopc: make(chan struct{})}
+	cfg := &e.cfg
+	defer func() {
+		if e == nil || err == nil {
+			return
+		}
+		if !serving {
+			// errored before starting gRPC server for serveCtx.serversC
+			for _, sctx := range e.sctxs {
+				sctx.close()
+			}
+		}
+		e.Close()
+		e = nil
+	}()
+
+	if !cfg.SocketOpts.Empty() {
+		cfg.logger.Info(
+			"configuring socket options",
+			zap.Bool("reuse-address", cfg.SocketOpts.ReuseAddress),
+			zap.Bool("reuse-port", cfg.SocketOpts.ReusePort),
+		)
+	}
+	e.cfg.logger.Info(
+		"configuring peer listeners",
+		zap.Strings("listen-peer-urls", e.cfg.getListenPeerURLs()),
+	)
+	if e.Peers, err = configurePeerListeners(cfg); err != nil {
+		return e, err
+	}
+
+	e.cfg.logger.Info(
+		"configuring client listeners",
+		zap.Strings("listen-client-urls", e.cfg.getListenClientURLs()),
+	)
+	if e.sctxs, err = configureClientListeners(cfg); err != nil {
+		return e, err
+	}
+
+	for _, sctx := range e.sctxs {
+		e.Clients = append(e.Clients, sctx.l)
+	}
+
+	var (
+		urlsmap types.URLsMap
+		token   string
+	)
+	memberInitialized := true
+	if !isMemberInitialized(cfg) {
+		memberInitialized = false
+		urlsmap, token, err = cfg.PeerURLsMapAndToken("etcd")
+		if err != nil {
+			return e, fmt.Errorf("error setting up initial cluster: %w", err)
+		}
+	}
+
+	// AutoCompactionRetention defaults to "0" if not set.
+	if len(cfg.AutoCompactionRetention) == 0 {
+		cfg.AutoCompactionRetention = "0"
+	}
+	autoCompactionRetention, err := parseCompactionRetention(cfg.AutoCompactionMode, cfg.AutoCompactionRetention)
+	if err != nil {
+		return e, err
+	}
+
+	backendFreelistType := parseBackendFreelistType(cfg.BackendFreelistType)
+
+	srvcfg := config.ServerConfig{
+		Name:                              cfg.Name,
+		ClientURLs:                        cfg.AdvertiseClientUrls,
+		PeerURLs:                          cfg.AdvertisePeerUrls,
+		DataDir:                           cfg.Dir,
+		DedicatedWALDir:                   cfg.WalDir,
+		SnapshotCount:                     cfg.SnapshotCount,
+		SnapshotCatchUpEntries:            cfg.SnapshotCatchUpEntries,
+		MaxSnapFiles:                      cfg.MaxSnapFiles,
+		MaxWALFiles:                       cfg.MaxWalFiles,
+		InitialPeerURLsMap:                urlsmap,
+		InitialClusterToken:               token,
+		DiscoveryURL:                      cfg.Durl,
+		DiscoveryProxy:                    cfg.Dproxy,
+		DiscoveryCfg:                      cfg.DiscoveryCfg,
+		NewCluster:                        cfg.IsNewCluster(),
+		PeerTLSInfo:                       cfg.PeerTLSInfo,
+		TickMs:                            cfg.TickMs,
+		ElectionTicks:                     cfg.ElectionTicks(),
+		InitialElectionTickAdvance:        cfg.InitialElectionTickAdvance,
+		AutoCompactionRetention:           autoCompactionRetention,
+		AutoCompactionMode:                cfg.AutoCompactionMode,
+		QuotaBackendBytes:                 cfg.QuotaBackendBytes,
+		BackendBatchLimit:                 cfg.BackendBatchLimit,
+		BackendFreelistType:               backendFreelistType,
+		BackendBatchInterval:              cfg.BackendBatchInterval,
+		MaxTxnOps:                         cfg.MaxTxnOps,
+		MaxRequestBytes:                   cfg.MaxRequestBytes,
+		MaxConcurrentStreams:              cfg.MaxConcurrentStreams,
+		SocketOpts:                        cfg.SocketOpts,
+		StrictReconfigCheck:               cfg.StrictReconfigCheck,
+		ClientCertAuthEnabled:             cfg.ClientTLSInfo.ClientCertAuth,
+		AuthToken:                         cfg.AuthToken,
+		BcryptCost:                        cfg.BcryptCost,
+		TokenTTL:                          cfg.AuthTokenTTL,
+		CORS:                              cfg.CORS,
+		HostWhitelist:                     cfg.HostWhitelist,
+		CorruptCheckTime:                  cfg.CorruptCheckTime,
+		CompactHashCheckTime:              cfg.CompactHashCheckTime,
+		PreVote:                           cfg.PreVote,
+		Logger:                            cfg.logger,
+		ForceNewCluster:                   cfg.ForceNewCluster,
+		EnableGRPCGateway:                 cfg.EnableGRPCGateway,
+		EnableDistributedTracing:          cfg.EnableDistributedTracing,
+		UnsafeNoFsync:                     cfg.UnsafeNoFsync,
+		CompactionBatchLimit:              cfg.CompactionBatchLimit,
+		CompactionSleepInterval:           cfg.CompactionSleepInterval,
+		WatchProgressNotifyInterval:       cfg.WatchProgressNotifyInterval,
+		DowngradeCheckTime:                cfg.DowngradeCheckTime,
+		WarningApplyDuration:              cfg.WarningApplyDuration,
+		WarningUnaryRequestDuration:       cfg.WarningUnaryRequestDuration,
+		MemoryMlock:                       cfg.MemoryMlock,
+		BootstrapDefragThresholdMegabytes: cfg.BootstrapDefragThresholdMegabytes,
+		MaxLearners:                       cfg.MaxLearners,
+		V2Deprecation:                     cfg.V2DeprecationEffective(),
+		ExperimentalLocalAddress:          cfg.InferLocalAddr(),
+		ServerFeatureGate:                 cfg.ServerFeatureGate,
+		Metrics:                           cfg.Metrics,
+	}
+
+	if srvcfg.EnableDistributedTracing {
+		tctx := context.Background()
+		tracingExporter, terr := newTracingExporter(tctx, cfg)
+		if terr != nil {
+			return e, terr
+		}
+		e.tracingExporterShutdown = func() {
+			tracingExporter.Close(tctx)
+		}
+		srvcfg.TracerOptions = tracingExporter.opts
+
+		e.cfg.logger.Info(
+			"distributed tracing setup enabled",
+		)
+	}
+
+	srvcfg.PeerTLSInfo.LocalAddr = srvcfg.ExperimentalLocalAddress
+
+	print(e.cfg.logger, *cfg, srvcfg, memberInitialized)
+
+	if e.Server, err = etcdserver.NewServer(srvcfg); err != nil {
+		return e, err
+	}
+
+	// buffer channel so goroutines on closed connections won't wait forever
+	e.errc = make(chan error, len(e.Peers)+len(e.Clients)+2*len(e.sctxs))
+
+	// newly started member ("memberInitialized==false")
+	// does not need corruption check
+	if memberInitialized && srvcfg.ServerFeatureGate.Enabled(features.InitialCorruptCheck) {
+		if err = e.Server.CorruptionChecker().InitialCheck(); err != nil {
+			// set "EtcdServer" to nil, so that it does not block on "EtcdServer.Close()"
+			// (nothing to close since rafthttp transports have not been started)
+
+			e.cfg.logger.Error("checkInitialHashKV failed", zap.Error(err))
+			e.Server.Cleanup()
+			e.Server = nil
+			return e, err
+		}
+	}
+	e.Server.Start()
+
+	e.servePeers()
+
+	e.serveClients()
+
+	if err = e.serveMetrics(); err != nil {
+		return e, err
+	}
+
+	e.cfg.logger.Info(
+		"now serving peer/client/metrics",
+		zap.String("local-member-id", e.Server.MemberID().String()),
+		zap.Strings("initial-advertise-peer-urls", e.cfg.getAdvertisePeerURLs()),
+		zap.Strings("listen-peer-urls", e.cfg.getListenPeerURLs()),
+		zap.Strings("advertise-client-urls", e.cfg.getAdvertiseClientURLs()),
+		zap.Strings("listen-client-urls", e.cfg.getListenClientURLs()),
+		zap.Strings("listen-metrics-urls", e.cfg.getMetricsURLs()),
+	)
+	serving = true
+	return e, nil
+}
+
+func print(lg *zap.Logger, ec Config, sc config.ServerConfig, memberInitialized bool) {
+	cors := make([]string, 0, len(ec.CORS))
+	for v := range ec.CORS {
+		cors = append(cors, v)
+	}
+	sort.Strings(cors)
+
+	hss := make([]string, 0, len(ec.HostWhitelist))
+	for v := range ec.HostWhitelist {
+		hss = append(hss, v)
+	}
+	sort.Strings(hss)
+
+	quota := ec.QuotaBackendBytes
+	if quota == 0 {
+		quota = storage.DefaultQuotaBytes
+	}
+
+	lg.Info(
+		"starting an etcd server",
+		zap.String("etcd-version", version.Version),
+		zap.String("git-sha", version.GitSHA),
+		zap.String("go-version", runtime.Version()),
+		zap.String("go-os", runtime.GOOS),
+		zap.String("go-arch", runtime.GOARCH),
+		zap.Int("max-cpu-set", runtime.GOMAXPROCS(0)),
+		zap.Int("max-cpu-available", runtime.NumCPU()),
+		zap.Bool("member-initialized", memberInitialized),
+		zap.String("name", sc.Name),
+		zap.String("data-dir", sc.DataDir),
+		zap.String("wal-dir", ec.WalDir),
+		zap.String("wal-dir-dedicated", sc.DedicatedWALDir),
+		zap.String("member-dir", sc.MemberDir()),
+		zap.Bool("force-new-cluster", sc.ForceNewCluster),
+		zap.String("heartbeat-interval", fmt.Sprintf("%v", time.Duration(sc.TickMs)*time.Millisecond)),
+		zap.String("election-timeout", fmt.Sprintf("%v", time.Duration(sc.ElectionTicks*int(sc.TickMs))*time.Millisecond)),
+		zap.Bool("initial-election-tick-advance", sc.InitialElectionTickAdvance),
+		zap.Uint64("snapshot-count", sc.SnapshotCount),
+		zap.Uint("max-wals", sc.MaxWALFiles),
+		zap.Uint("max-snapshots", sc.MaxSnapFiles),
+		zap.Uint64("snapshot-catchup-entries", sc.SnapshotCatchUpEntries),
+		zap.Strings("initial-advertise-peer-urls", ec.getAdvertisePeerURLs()),
+		zap.Strings("listen-peer-urls", ec.getListenPeerURLs()),
+		zap.Strings("advertise-client-urls", ec.getAdvertiseClientURLs()),
+		zap.Strings("listen-client-urls", ec.getListenClientURLs()),
+		zap.Strings("listen-metrics-urls", ec.getMetricsURLs()),
+		zap.String("experimental-local-address", sc.ExperimentalLocalAddress),
+		zap.Strings("cors", cors),
+		zap.Strings("host-whitelist", hss),
+		zap.String("initial-cluster", sc.InitialPeerURLsMap.String()),
+		zap.String("initial-cluster-state", ec.ClusterState),
+		zap.String("initial-cluster-token", sc.InitialClusterToken),
+		zap.Int64("quota-backend-bytes", quota),
+		zap.Uint("max-request-bytes", sc.MaxRequestBytes),
+		zap.Uint32("max-concurrent-streams", sc.MaxConcurrentStreams),
+
+		zap.Bool("pre-vote", sc.PreVote),
+		zap.String(ServerFeatureGateFlagName, sc.ServerFeatureGate.String()),
+		zap.Bool("initial-corrupt-check", sc.InitialCorruptCheck),
+		zap.String("corrupt-check-time-interval", sc.CorruptCheckTime.String()),
+		zap.Duration("compact-check-time-interval", sc.CompactHashCheckTime),
+		zap.String("auto-compaction-mode", sc.AutoCompactionMode),
+		zap.Duration("auto-compaction-retention", sc.AutoCompactionRetention),
+		zap.String("auto-compaction-interval", sc.AutoCompactionRetention.String()),
+		zap.String("discovery-url", sc.DiscoveryURL),
+		zap.String("discovery-proxy", sc.DiscoveryProxy),
+
+		zap.String("discovery-token", sc.DiscoveryCfg.Token),
+		zap.String("discovery-endpoints", strings.Join(sc.DiscoveryCfg.Endpoints, ",")),
+		zap.String("discovery-dial-timeout", sc.DiscoveryCfg.DialTimeout.String()),
+		zap.String("discovery-request-timeout", sc.DiscoveryCfg.RequestTimeout.String()),
+		zap.String("discovery-keepalive-time", sc.DiscoveryCfg.KeepAliveTime.String()),
+		zap.String("discovery-keepalive-timeout", sc.DiscoveryCfg.KeepAliveTimeout.String()),
+		zap.Bool("discovery-insecure-transport", sc.DiscoveryCfg.Secure.InsecureTransport),
+		zap.Bool("discovery-insecure-skip-tls-verify", sc.DiscoveryCfg.Secure.InsecureSkipVerify),
+		zap.String("discovery-cert", sc.DiscoveryCfg.Secure.Cert),
+		zap.String("discovery-key", sc.DiscoveryCfg.Secure.Key),
+		zap.String("discovery-cacert", sc.DiscoveryCfg.Secure.Cacert),
+		zap.String("discovery-user", sc.DiscoveryCfg.Auth.Username),
+
+		zap.String("downgrade-check-interval", sc.DowngradeCheckTime.String()),
+		zap.Int("max-learners", sc.MaxLearners),
+
+		zap.String("v2-deprecation", string(ec.V2Deprecation)),
+	)
+}
+
+// Config returns the current configuration.
+func (e *Etcd) Config() Config {
+	return e.cfg
+}
+
+// Close gracefully shuts down all servers/listeners.
+// Client requests will be terminated with request timeout.
+// After timeout, enforce remaning requests be closed immediately.
+//
+// The rough workflow to shut down etcd:
+//  1. close the `stopc` channel, so that all error handlers (child
+//     goroutines) won't send back any errors anymore;
+//  2. stop the http and grpc servers gracefully, within request timeout;
+//  3. close all client and metrics listeners, so that etcd server
+//     stops receiving any new connection;
+//  4. call the cancel function to close the gateway context, so that
+//     all gateway connections are closed.
+//  5. stop etcd server gracefully, and ensure the main raft loop
+//     goroutine is stopped;
+//  6. stop all peer listeners, so that it stops receiving peer connections
+//     and messages (wait up to 1-second);
+//  7. wait for all child goroutines (i.e. client handlers, peer handlers
+//     and metrics handlers) to exit;
+//  8. close the `errc` channel to release the resource. Note that it's only
+//     safe to close the `errc` after step 7 above is done, otherwise the
+//     child goroutines may send errors back to already closed `errc` channel.
+func (e *Etcd) Close() {
+	fields := []zap.Field{
+		zap.String("name", e.cfg.Name),
+		zap.String("data-dir", e.cfg.Dir),
+		zap.Strings("advertise-peer-urls", e.cfg.getAdvertisePeerURLs()),
+		zap.Strings("advertise-client-urls", e.cfg.getAdvertiseClientURLs()),
+	}
+	lg := e.GetLogger()
+	lg.Info("closing etcd server", fields...)
+	defer func() {
+		lg.Info("closed etcd server", fields...)
+		verify.MustVerifyIfEnabled(verify.Config{
+			Logger:     lg,
+			DataDir:    e.cfg.Dir,
+			ExactIndex: false,
+		})
+		lg.Sync()
+	}()
+
+	e.closeOnce.Do(func() {
+		close(e.stopc)
+	})
+
+	// close client requests with request timeout
+	timeout := 2 * time.Second
+	if e.Server != nil {
+		timeout = e.Server.Cfg.ReqTimeout()
+	}
+	for _, sctx := range e.sctxs {
+		for ss := range sctx.serversC {
+			ctx, cancel := context.WithTimeout(context.Background(), timeout)
+			stopServers(ctx, ss)
+			cancel()
+		}
+	}
+
+	for _, sctx := range e.sctxs {
+		sctx.cancel()
+	}
+
+	for i := range e.Clients {
+		if e.Clients[i] != nil {
+			e.Clients[i].Close()
+		}
+	}
+
+	for i := range e.metricsListeners {
+		e.metricsListeners[i].Close()
+	}
+
+	// shutdown tracing exporter
+	if e.tracingExporterShutdown != nil {
+		e.tracingExporterShutdown()
+	}
+
+	// close rafthttp transports
+	if e.Server != nil {
+		e.Server.Stop()
+	}
+
+	// close all idle connections in peer handler (wait up to 1-second)
+	for i := range e.Peers {
+		if e.Peers[i] != nil && e.Peers[i].close != nil {
+			ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+			e.Peers[i].close(ctx)
+			cancel()
+		}
+	}
+	if e.errc != nil {
+		e.wg.Wait()
+		close(e.errc)
+	}
+}
+
+func stopServers(ctx context.Context, ss *servers) {
+	// first, close the http.Server
+	if ss.http != nil {
+		ss.http.Shutdown(ctx)
+	}
+	if ss.grpc == nil {
+		return
+	}
+	// do not grpc.Server.GracefulStop when grpc runs under http server
+	// See https://github.com/grpc/grpc-go/issues/1384#issuecomment-317124531
+	// and https://github.com/etcd-io/etcd/issues/8916
+	if ss.secure && ss.http != nil {
+		ss.grpc.Stop()
+		return
+	}
+
+	ch := make(chan struct{})
+	go func() {
+		defer close(ch)
+		// close listeners to stop accepting new connections,
+		// will block on any existing transports
+		ss.grpc.GracefulStop()
+	}()
+
+	// wait until all pending RPCs are finished
+	select {
+	case <-ch:
+	case <-ctx.Done():
+		// took too long, manually close open transports
+		// e.g. watch streams
+		ss.grpc.Stop()
+
+		// concurrent GracefulStop should be interrupted
+		<-ch
+	}
+}
+
+// Err - return channel used to report errors during etcd run/shutdown.
+// Since etcd 3.5 the channel is being closed when the etcd is over.
+func (e *Etcd) Err() <-chan error {
+	return e.errc
+}
+
+func configurePeerListeners(cfg *Config) (peers []*peerListener, err error) {
+	if err = updateCipherSuites(&cfg.PeerTLSInfo, cfg.CipherSuites); err != nil {
+		return nil, err
+	}
+	if err = cfg.PeerSelfCert(); err != nil {
+		cfg.logger.Fatal("failed to get peer self-signed certs", zap.Error(err))
+	}
+	updateMinMaxVersions(&cfg.PeerTLSInfo, cfg.TlsMinVersion, cfg.TlsMaxVersion)
+	if !cfg.PeerTLSInfo.Empty() {
+		cfg.logger.Info(
+			"starting with peer TLS",
+			zap.String("tls-info", fmt.Sprintf("%+v", cfg.PeerTLSInfo)),
+			zap.Strings("cipher-suites", cfg.CipherSuites),
+		)
+	}
+
+	peers = make([]*peerListener, len(cfg.ListenPeerUrls))
+	defer func() {
+		if err == nil {
+			return
+		}
+		for i := range peers {
+			if peers[i] != nil && peers[i].close != nil {
+				cfg.logger.Warn(
+					"closing peer listener",
+					zap.String("address", cfg.ListenPeerUrls[i].String()),
+					zap.Error(err),
+				)
+				ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+				peers[i].close(ctx)
+				cancel()
+			}
+		}
+	}()
+
+	for i, u := range cfg.ListenPeerUrls {
+		if u.Scheme == "http" {
+			if !cfg.PeerTLSInfo.Empty() {
+				cfg.logger.Warn("scheme is HTTP while key and cert files are present; ignoring key and cert files", zap.String("peer-url", u.String()))
+			}
+			if cfg.PeerTLSInfo.ClientCertAuth {
+				cfg.logger.Warn("scheme is HTTP while --peer-client-cert-auth is enabled; ignoring client cert auth for this URL", zap.String("peer-url", u.String()))
+			}
+		}
+		peers[i] = &peerListener{close: func(context.Context) error { return nil }}
+		peers[i].Listener, err = transport.NewListenerWithOpts(u.Host, u.Scheme,
+			transport.WithTLSInfo(&cfg.PeerTLSInfo),
+			transport.WithSocketOpts(&cfg.SocketOpts),
+			transport.WithTimeout(rafthttp.ConnReadTimeout, rafthttp.ConnWriteTimeout),
+		)
+		if err != nil {
+			cfg.logger.Error("creating peer listener failed", zap.Error(err))
+			return nil, err
+		}
+		// once serve, overwrite with 'http.Server.Shutdown'
+		peers[i].close = func(context.Context) error {
+			return peers[i].Listener.Close()
+		}
+	}
+	return peers, nil
+}
+
+// configure peer handlers after rafthttp.Transport started
+func (e *Etcd) servePeers() {
+	ph := etcdhttp.NewPeerHandler(e.GetLogger(), e.Server)
+
+	for _, p := range e.Peers {
+		u := p.Listener.Addr().String()
+		m := cmux.New(p.Listener)
+		srv := &http.Server{
+			Handler:     ph,
+			ReadTimeout: 5 * time.Minute,
+			ErrorLog:    defaultLog.New(io.Discard, "", 0), // do not log user error
+		}
+		go srv.Serve(m.Match(cmux.Any()))
+		p.serve = func() error {
+			e.cfg.logger.Info(
+				"cmux::serve",
+				zap.String("address", u),
+			)
+			return m.Serve()
+		}
+		p.close = func(ctx context.Context) error {
+			// gracefully shutdown http.Server
+			// close open listeners, idle connections
+			// until context cancel or time-out
+			e.cfg.logger.Info(
+				"stopping serving peer traffic",
+				zap.String("address", u),
+			)
+			srv.Shutdown(ctx)
+			e.cfg.logger.Info(
+				"stopped serving peer traffic",
+				zap.String("address", u),
+			)
+			m.Close()
+			return nil
+		}
+	}
+
+	// start peer servers in a goroutine
+	for _, pl := range e.Peers {
+		l := pl
+		e.startHandler(func() error {
+			u := l.Addr().String()
+			e.cfg.logger.Info(
+				"serving peer traffic",
+				zap.String("address", u),
+			)
+			return l.serve()
+		})
+	}
+}
+
+func configureClientListeners(cfg *Config) (sctxs map[string]*serveCtx, err error) {
+	if err = updateCipherSuites(&cfg.ClientTLSInfo, cfg.CipherSuites); err != nil {
+		return nil, err
+	}
+	if err = cfg.ClientSelfCert(); err != nil {
+		cfg.logger.Fatal("failed to get client self-signed certs", zap.Error(err))
+	}
+	updateMinMaxVersions(&cfg.ClientTLSInfo, cfg.TlsMinVersion, cfg.TlsMaxVersion)
+	if cfg.EnablePprof {
+		cfg.logger.Info("pprof is enabled", zap.String("path", debugutil.HTTPPrefixPProf))
+	}
+
+	sctxs = make(map[string]*serveCtx)
+	for _, u := range append(cfg.ListenClientUrls, cfg.ListenClientHttpUrls...) {
+		if u.Scheme == "http" || u.Scheme == "unix" {
+			if !cfg.ClientTLSInfo.Empty() {
+				cfg.logger.Warn("scheme is http or unix while key and cert files are present; ignoring key and cert files", zap.String("client-url", u.String()))
+			}
+			if cfg.ClientTLSInfo.ClientCertAuth {
+				cfg.logger.Warn("scheme is http or unix while --client-cert-auth is enabled; ignoring client cert auth for this URL", zap.String("client-url", u.String()))
+			}
+		}
+		if (u.Scheme == "https" || u.Scheme == "unixs") && cfg.ClientTLSInfo.Empty() {
+			return nil, fmt.Errorf("TLS key/cert (--cert-file, --key-file) must be provided for client url %s with HTTPS scheme", u.String())
+		}
+	}
+
+	for _, u := range cfg.ListenClientUrls {
+		addr, secure, network := resolveURL(u)
+		sctx := sctxs[addr]
+		if sctx == nil {
+			sctx = newServeCtx(cfg.logger)
+			sctxs[addr] = sctx
+		}
+		sctx.secure = sctx.secure || secure
+		sctx.insecure = sctx.insecure || !secure
+		sctx.scheme = u.Scheme
+		sctx.addr = addr
+		sctx.network = network
+	}
+	for _, u := range cfg.ListenClientHttpUrls {
+		addr, secure, network := resolveURL(u)
+
+		sctx := sctxs[addr]
+		if sctx == nil {
+			sctx = newServeCtx(cfg.logger)
+			sctxs[addr] = sctx
+		} else if !sctx.httpOnly {
+			return nil, fmt.Errorf("cannot bind both --listen-client-urls and --listen-client-http-urls on the same url %s", u.String())
+		}
+		sctx.secure = sctx.secure || secure
+		sctx.insecure = sctx.insecure || !secure
+		sctx.scheme = u.Scheme
+		sctx.addr = addr
+		sctx.network = network
+		sctx.httpOnly = true
+	}
+
+	for _, sctx := range sctxs {
+		if sctx.l, err = transport.NewListenerWithOpts(sctx.addr, sctx.scheme,
+			transport.WithSocketOpts(&cfg.SocketOpts),
+			transport.WithSkipTLSInfoCheck(true),
+		); err != nil {
+			return nil, err
+		}
+		// net.Listener will rewrite ipv4 0.0.0.0 to ipv6 [::], breaking
+		// hosts that disable ipv6. So, use the address given by the user.
+
+		if fdLimit, fderr := runtimeutil.FDLimit(); fderr == nil {
+			if fdLimit <= reservedInternalFDNum {
+				cfg.logger.Fatal(
+					"file descriptor limit of etcd process is too low; please set higher",
+					zap.Uint64("limit", fdLimit),
+					zap.Int("recommended-limit", reservedInternalFDNum),
+				)
+			}
+			sctx.l = transport.LimitListener(sctx.l, int(fdLimit-reservedInternalFDNum))
+		}
+
+		defer func(sctx *serveCtx) {
+			if err == nil || sctx.l == nil {
+				return
+			}
+			sctx.l.Close()
+			cfg.logger.Warn(
+				"closing peer listener",
+				zap.String("address", sctx.addr),
+				zap.Error(err),
+			)
+		}(sctx)
+		for k := range cfg.UserHandlers {
+			sctx.userHandlers[k] = cfg.UserHandlers[k]
+		}
+		sctx.serviceRegister = cfg.ServiceRegister
+		if cfg.EnablePprof || cfg.LogLevel == "debug" {
+			sctx.registerPprof()
+		}
+		if cfg.LogLevel == "debug" {
+			sctx.registerTrace()
+		}
+	}
+	return sctxs, nil
+}
+
+func resolveURL(u url.URL) (addr string, secure bool, network string) {
+	addr = u.Host
+	network = "tcp"
+	if u.Scheme == "unix" || u.Scheme == "unixs" {
+		addr = u.Host + u.Path
+		network = "unix"
+	}
+	secure = u.Scheme == "https" || u.Scheme == "unixs"
+	return addr, secure, network
+}
+
+func (e *Etcd) serveClients() {
+	if !e.cfg.ClientTLSInfo.Empty() {
+		e.cfg.logger.Info(
+			"starting with client TLS",
+			zap.String("tls-info", fmt.Sprintf("%+v", e.cfg.ClientTLSInfo)),
+			zap.Strings("cipher-suites", e.cfg.CipherSuites),
+		)
+	}
+
+	// Start a client server goroutine for each listen address
+	mux := http.NewServeMux()
+	etcdhttp.HandleDebug(mux)
+	etcdhttp.HandleVersion(mux, e.Server)
+	etcdhttp.HandleMetrics(mux)
+	etcdhttp.HandleHealth(e.cfg.logger, mux, e.Server)
+
+	var gopts []grpc.ServerOption
+	if e.cfg.GRPCKeepAliveMinTime > time.Duration(0) {
+		gopts = append(gopts, grpc.KeepaliveEnforcementPolicy(keepalive.EnforcementPolicy{
+			MinTime:             e.cfg.GRPCKeepAliveMinTime,
+			PermitWithoutStream: false,
+		}))
+	}
+	if e.cfg.GRPCKeepAliveInterval > time.Duration(0) &&
+		e.cfg.GRPCKeepAliveTimeout > time.Duration(0) {
+		gopts = append(gopts, grpc.KeepaliveParams(keepalive.ServerParameters{
+			Time:    e.cfg.GRPCKeepAliveInterval,
+			Timeout: e.cfg.GRPCKeepAliveTimeout,
+		}))
+	}
+	gopts = append(gopts, e.cfg.GRPCAdditionalServerOptions...)
+
+	splitHTTP := false
+	for _, sctx := range e.sctxs {
+		if sctx.httpOnly {
+			splitHTTP = true
+		}
+	}
+
+	// start client servers in each goroutine
+	for _, sctx := range e.sctxs {
+		s := sctx
+		e.startHandler(func() error {
+			return s.serve(e.Server, &e.cfg.ClientTLSInfo, mux, e.errHandler, e.grpcGatewayDial(splitHTTP), splitHTTP, gopts...)
+		})
+	}
+}
+
+func (e *Etcd) grpcGatewayDial(splitHTTP bool) (grpcDial func(ctx context.Context) (*grpc.ClientConn, error)) {
+	if !e.cfg.EnableGRPCGateway {
+		return nil
+	}
+	sctx := e.pickGRPCGatewayServeContext(splitHTTP)
+	addr := sctx.addr
+	if network := sctx.network; network == "unix" {
+		// explicitly define unix network for gRPC socket support
+		addr = fmt.Sprintf("%s:%s", network, addr)
+	}
+	opts := []grpc.DialOption{grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(math.MaxInt32))}
+	if sctx.secure {
+		tlscfg, tlsErr := e.cfg.ClientTLSInfo.ServerConfig()
+		if tlsErr != nil {
+			return func(ctx context.Context) (*grpc.ClientConn, error) {
+				return nil, tlsErr
+			}
+		}
+		dtls := tlscfg.Clone()
+		// trust local server
+		dtls.InsecureSkipVerify = true
+		opts = append(opts, grpc.WithTransportCredentials(credentials.NewTransportCredential(dtls)))
+	} else {
+		opts = append(opts, grpc.WithTransportCredentials(insecure.NewCredentials()))
+	}
+
+	return func(ctx context.Context) (*grpc.ClientConn, error) {
+		conn, err := grpc.DialContext(ctx, addr, opts...)
+		if err != nil {
+			sctx.lg.Error("grpc gateway failed to dial", zap.String("addr", addr), zap.Error(err))
+			return nil, err
+		}
+		return conn, err
+	}
+}
+
+func (e *Etcd) pickGRPCGatewayServeContext(splitHTTP bool) *serveCtx {
+	for _, sctx := range e.sctxs {
+		if !splitHTTP || !sctx.httpOnly {
+			return sctx
+		}
+	}
+	panic("Expect at least one context able to serve grpc")
+}
+
+var ErrMissingClientTLSInfoForMetricsURL = errors.New("client TLS key/cert (--cert-file, --key-file) must be provided for metrics secure url")
+
+func (e *Etcd) createMetricsListener(murl url.URL) (net.Listener, error) {
+	tlsInfo := &e.cfg.ClientTLSInfo
+	switch murl.Scheme {
+	case "http":
+		tlsInfo = nil
+	case "https", "unixs":
+		if e.cfg.ClientTLSInfo.Empty() {
+			return nil, ErrMissingClientTLSInfoForMetricsURL
+		}
+	}
+	return transport.NewListenerWithOpts(murl.Host, murl.Scheme,
+		transport.WithTLSInfo(tlsInfo),
+		transport.WithSocketOpts(&e.cfg.SocketOpts),
+	)
+}
+
+func (e *Etcd) serveMetrics() (err error) {
+	if len(e.cfg.ListenMetricsUrls) > 0 {
+		metricsMux := http.NewServeMux()
+		etcdhttp.HandleMetrics(metricsMux)
+		etcdhttp.HandleHealth(e.cfg.logger, metricsMux, e.Server)
+
+		for _, murl := range e.cfg.ListenMetricsUrls {
+			u := murl
+			ml, err := e.createMetricsListener(murl)
+			if err != nil {
+				return err
+			}
+			e.metricsListeners = append(e.metricsListeners, ml)
+
+			e.startHandler(func() error {
+				e.cfg.logger.Info(
+					"serving metrics",
+					zap.String("address", u.String()),
+				)
+				return http.Serve(ml, metricsMux)
+			})
+		}
+	}
+	return nil
+}
+
+func (e *Etcd) startHandler(handler func() error) {
+	// start each handler in a separate goroutine
+	e.wg.Add(1)
+	go func() {
+		defer e.wg.Done()
+		e.errHandler(handler())
+	}()
+}
+
+func (e *Etcd) errHandler(err error) {
+	if err != nil {
+		e.GetLogger().Error("setting up serving from embedded etcd failed.", zap.Error(err))
+	}
+	select {
+	case <-e.stopc:
+		return
+	default:
+	}
+	select {
+	case <-e.stopc:
+	case e.errc <- err:
+	}
+}
+
+// GetLogger returns the logger.
+func (e *Etcd) GetLogger() *zap.Logger {
+	e.cfg.loggerMu.RLock()
+	l := e.cfg.logger
+	e.cfg.loggerMu.RUnlock()
+	return l
+}
+
+func parseCompactionRetention(mode, retention string) (ret time.Duration, err error) {
+	h, err := strconv.Atoi(retention)
+	if err == nil && h >= 0 {
+		switch mode {
+		case CompactorModeRevision:
+			ret = time.Duration(int64(h))
+		case CompactorModePeriodic:
+			ret = time.Duration(int64(h)) * time.Hour
+		case "":
+			return 0, errors.New("--auto-compaction-mode is undefined")
+		}
+	} else {
+		// periodic compaction
+		ret, err = time.ParseDuration(retention)
+		if err != nil {
+			return 0, fmt.Errorf("error parsing CompactionRetention: %w", err)
+		}
+	}
+	return ret, nil
+}