diff --git a/third_party/BUILD b/third_party/BUILD
index a6b23dbb6724d..801e43d550120 100644
--- a/third_party/BUILD
+++ b/third_party/BUILD
@@ -13,6 +13,8 @@ filegroup(
     name = "all-srcs",
     srcs = [
         ":package-srcs",
+        "//third_party/forked/etcd221/pkg/fileutil:all-srcs",
+        "//third_party/forked/etcd221/wal:all-srcs",
         "//third_party/forked/etcd237/pkg/fileutil:all-srcs",
         "//third_party/forked/etcd237/wal:all-srcs",
         "//third_party/forked/golang/expansion:all-srcs",
diff --git a/third_party/forked/etcd221/README.md b/third_party/forked/etcd221/README.md
new file mode 100644
index 0000000000000..548aee2a53495
--- /dev/null
+++ b/third_party/forked/etcd221/README.md
@@ -0,0 +1 @@
+Forked from etcd 2.2 release branch to support migration from 3.0 WAL to 2.2 WAL format
diff --git a/third_party/forked/etcd221/pkg/fileutil/BUILD b/third_party/forked/etcd221/pkg/fileutil/BUILD
new file mode 100644
index 0000000000000..1749bf95c9363
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/BUILD
@@ -0,0 +1,46 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+    "go_test",
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = [
+        "fileutil_test.go",
+        "lock_test.go",
+        "preallocate_test.go",
+        "purge_test.go",
+    ],
+    library = ":go_default_library",
+    tags = ["automanaged"],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "fileutil.go",
+        "lock_unix.go",
+        "preallocate.go",
+        "purge.go",
+    ],
+    tags = ["automanaged"],
+    deps = ["//vendor:github.com/coreos/pkg/capnslog"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+)
diff --git a/third_party/forked/etcd221/pkg/fileutil/fileutil.go b/third_party/forked/etcd221/pkg/fileutil/fileutil.go
new file mode 100644
index 0000000000000..b052553c11dd5
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/fileutil.go
@@ -0,0 +1,57 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 fileutil
+
+import (
+	"io/ioutil"
+	"os"
+	"path"
+	"sort"
+
+	"github.com/coreos/pkg/capnslog"
+)
+
+const (
+	privateFileMode = 0600
+)
+
+var (
+	plog = capnslog.NewPackageLogger("github.com/coreos/etcd/pkg", "fileutil")
+)
+
+// IsDirWriteable checks if dir is writable by writing and removing a file
+// to dir. It returns nil if dir is writable.
+func IsDirWriteable(dir string) error {
+	f := path.Join(dir, ".touch")
+	if err := ioutil.WriteFile(f, []byte(""), privateFileMode); err != nil {
+		return err
+	}
+	return os.Remove(f)
+}
+
+// ReadDir returns the filenames in the given directory in sorted order.
+func ReadDir(dirpath string) ([]string, error) {
+	dir, err := os.Open(dirpath)
+	if err != nil {
+		return nil, err
+	}
+	defer dir.Close()
+	names, err := dir.Readdirnames(-1)
+	if err != nil {
+		return nil, err
+	}
+	sort.Strings(names)
+	return names, nil
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/fileutil_test.go b/third_party/forked/etcd221/pkg/fileutil/fileutil_test.go
new file mode 100644
index 0000000000000..e5a9eb24d41f5
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/fileutil_test.go
@@ -0,0 +1,67 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 fileutil
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"reflect"
+	"testing"
+)
+
+func TestIsDirWriteable(t *testing.T) {
+	tmpdir, err := ioutil.TempDir("", "")
+	if err != nil {
+		t.Fatalf("unexpected ioutil.TempDir error: %v", err)
+	}
+	defer os.RemoveAll(tmpdir)
+	if err := IsDirWriteable(tmpdir); err != nil {
+		t.Fatalf("unexpected IsDirWriteable error: %v", err)
+	}
+	if err := os.Chmod(tmpdir, 0444); err != nil {
+		t.Fatalf("unexpected os.Chmod error: %v", err)
+	}
+	if err := IsDirWriteable(tmpdir); err == nil {
+		t.Fatalf("expected IsDirWriteable to error")
+	}
+}
+
+func TestReadDir(t *testing.T) {
+	tmpdir, err := ioutil.TempDir("", "")
+	defer os.RemoveAll(tmpdir)
+	if err != nil {
+		t.Fatalf("unexpected ioutil.TempDir error: %v", err)
+	}
+	files := []string{"def", "abc", "xyz", "ghi"}
+	for _, f := range files {
+		var fh *os.File
+		fh, err = os.Create(filepath.Join(tmpdir, f))
+		if err != nil {
+			t.Fatalf("error creating file: %v", err)
+		}
+		if err := fh.Close(); err != nil {
+			t.Fatalf("error closing file: %v", err)
+		}
+	}
+	fs, err := ReadDir(tmpdir)
+	if err != nil {
+		t.Fatalf("error calling ReadDir: %v", err)
+	}
+	wfs := []string{"abc", "def", "ghi", "xyz"}
+	if !reflect.DeepEqual(fs, wfs) {
+		t.Fatalf("ReadDir: got %v, want %v", fs, wfs)
+	}
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/lock_plan9.go b/third_party/forked/etcd221/pkg/fileutil/lock_plan9.go
new file mode 100644
index 0000000000000..311288de03198
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/lock_plan9.go
@@ -0,0 +1,90 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 fileutil
+
+import (
+	"errors"
+	"os"
+	"syscall"
+	"time"
+)
+
+var (
+	ErrLocked = errors.New("file already locked")
+)
+
+type Lock interface {
+	Name() string
+	TryLock() error
+	Lock() error
+	Unlock() error
+	Destroy() error
+}
+
+type lock struct {
+	fname string
+	file  *os.File
+}
+
+func (l *lock) Name() string {
+	return l.fname
+}
+
+// TryLock acquires exclusivity on the lock without blocking
+func (l *lock) TryLock() error {
+	err := os.Chmod(l.fname, syscall.DMEXCL|0600)
+	if err != nil {
+		return err
+	}
+
+	f, err := os.Open(l.fname)
+	if err != nil {
+		return ErrLocked
+	}
+
+	l.file = f
+	return nil
+}
+
+// Lock acquires exclusivity on the lock with blocking
+func (l *lock) Lock() error {
+	err := os.Chmod(l.fname, syscall.DMEXCL|0600)
+	if err != nil {
+		return err
+	}
+
+	for {
+		f, err := os.Open(l.fname)
+		if err == nil {
+			l.file = f
+			return nil
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+}
+
+// Unlock unlocks the lock
+func (l *lock) Unlock() error {
+	return l.file.Close()
+}
+
+func (l *lock) Destroy() error {
+	return nil
+}
+
+func NewLock(file string) (Lock, error) {
+	l := &lock{fname: file}
+	return l, nil
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/lock_solaris.go b/third_party/forked/etcd221/pkg/fileutil/lock_solaris.go
new file mode 100644
index 0000000000000..1929bd1fc8c10
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/lock_solaris.go
@@ -0,0 +1,98 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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.
+
+// +build solaris
+
+package fileutil
+
+import (
+	"errors"
+	"os"
+	"syscall"
+)
+
+var (
+	ErrLocked = errors.New("file already locked")
+)
+
+type Lock interface {
+	Name() string
+	TryLock() error
+	Lock() error
+	Unlock() error
+	Destroy() error
+}
+
+type lock struct {
+	fd   int
+	file *os.File
+}
+
+func (l *lock) Name() string {
+	return l.file.Name()
+}
+
+// TryLock acquires exclusivity on the lock without blocking
+func (l *lock) TryLock() error {
+	var lock syscall.Flock_t
+	lock.Start = 0
+	lock.Len = 0
+	lock.Pid = 0
+	lock.Type = syscall.F_WRLCK
+	lock.Whence = 0
+	lock.Pid = 0
+	err := syscall.FcntlFlock(uintptr(l.fd), syscall.F_SETLK, &lock)
+	if err != nil && err == syscall.EAGAIN {
+		return ErrLocked
+	}
+	return err
+}
+
+// Lock acquires exclusivity on the lock without blocking
+func (l *lock) Lock() error {
+	var lock syscall.Flock_t
+	lock.Start = 0
+	lock.Len = 0
+	lock.Type = syscall.F_WRLCK
+	lock.Whence = 0
+	lock.Pid = 0
+	return syscall.FcntlFlock(uintptr(l.fd), syscall.F_SETLK, &lock)
+}
+
+// Unlock unlocks the lock
+func (l *lock) Unlock() error {
+	var lock syscall.Flock_t
+	lock.Start = 0
+	lock.Len = 0
+	lock.Type = syscall.F_UNLCK
+	lock.Whence = 0
+	err := syscall.FcntlFlock(uintptr(l.fd), syscall.F_SETLK, &lock)
+	if err != nil && err == syscall.EAGAIN {
+		return ErrLocked
+	}
+	return err
+}
+
+func (l *lock) Destroy() error {
+	return l.file.Close()
+}
+
+func NewLock(file string) (Lock, error) {
+	f, err := os.OpenFile(file, os.O_WRONLY, 0600)
+	if err != nil {
+		return nil, err
+	}
+	l := &lock{int(f.Fd()), f}
+	return l, nil
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/lock_test.go b/third_party/forked/etcd221/pkg/fileutil/lock_test.go
new file mode 100644
index 0000000000000..cda47deea41d4
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/lock_test.go
@@ -0,0 +1,96 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 fileutil
+
+import (
+	"io/ioutil"
+	"os"
+	"testing"
+	"time"
+)
+
+func TestLockAndUnlock(t *testing.T) {
+	f, err := ioutil.TempFile("", "lock")
+	if err != nil {
+		t.Fatal(err)
+	}
+	f.Close()
+	defer func() {
+		err := os.Remove(f.Name())
+		if err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	// lock the file
+	l, err := NewLock(f.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer l.Destroy()
+	err = l.Lock()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// try lock a locked file
+	dupl, err := NewLock(f.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+	err = dupl.TryLock()
+	if err != ErrLocked {
+		t.Errorf("err = %v, want %v", err, ErrLocked)
+	}
+
+	// unlock the file
+	err = l.Unlock()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// try lock the unlocked file
+	err = dupl.TryLock()
+	if err != nil {
+		t.Errorf("err = %v, want %v", err, nil)
+	}
+	defer dupl.Destroy()
+
+	// blocking on locked file
+	locked := make(chan struct{}, 1)
+	go func() {
+		l.Lock()
+		locked <- struct{}{}
+	}()
+
+	select {
+	case <-locked:
+		t.Error("unexpected unblocking")
+	case <-time.After(10 * time.Millisecond):
+	}
+
+	// unlock
+	err = dupl.Unlock()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// the previously blocked routine should be unblocked
+	select {
+	case <-locked:
+	case <-time.After(20 * time.Millisecond):
+		t.Error("unexpected blocking")
+	}
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/lock_unix.go b/third_party/forked/etcd221/pkg/fileutil/lock_unix.go
new file mode 100644
index 0000000000000..f6e69cc344dc7
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/lock_unix.go
@@ -0,0 +1,76 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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.
+
+// +build !windows,!plan9,!solaris
+
+package fileutil
+
+import (
+	"errors"
+	"os"
+	"syscall"
+)
+
+var (
+	ErrLocked = errors.New("file already locked")
+)
+
+type Lock interface {
+	Name() string
+	TryLock() error
+	Lock() error
+	Unlock() error
+	Destroy() error
+}
+
+type lock struct {
+	fd   int
+	file *os.File
+}
+
+func (l *lock) Name() string {
+	return l.file.Name()
+}
+
+// TryLock acquires exclusivity on the lock without blocking
+func (l *lock) TryLock() error {
+	err := syscall.Flock(l.fd, syscall.LOCK_EX|syscall.LOCK_NB)
+	if err != nil && err == syscall.EWOULDBLOCK {
+		return ErrLocked
+	}
+	return err
+}
+
+// Lock acquires exclusivity on the lock without blocking
+func (l *lock) Lock() error {
+	return syscall.Flock(l.fd, syscall.LOCK_EX)
+}
+
+// Unlock unlocks the lock
+func (l *lock) Unlock() error {
+	return syscall.Flock(l.fd, syscall.LOCK_UN)
+}
+
+func (l *lock) Destroy() error {
+	return l.file.Close()
+}
+
+func NewLock(file string) (Lock, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return nil, err
+	}
+	l := &lock{int(f.Fd()), f}
+	return l, nil
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/lock_windows.go b/third_party/forked/etcd221/pkg/fileutil/lock_windows.go
new file mode 100644
index 0000000000000..a0a928b90ad27
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/lock_windows.go
@@ -0,0 +1,71 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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.
+
+// +build windows
+
+package fileutil
+
+import (
+	"errors"
+	"os"
+)
+
+var (
+	ErrLocked = errors.New("file already locked")
+)
+
+type Lock interface {
+	Name() string
+	TryLock() error
+	Lock() error
+	Unlock() error
+	Destroy() error
+}
+
+type lock struct {
+	fd   int
+	file *os.File
+}
+
+func (l *lock) Name() string {
+	return l.file.Name()
+}
+
+// TryLock acquires exclusivity on the lock without blocking
+func (l *lock) TryLock() error {
+	return nil
+}
+
+// Lock acquires exclusivity on the lock without blocking
+func (l *lock) Lock() error {
+	return nil
+}
+
+// Unlock unlocks the lock
+func (l *lock) Unlock() error {
+	return nil
+}
+
+func (l *lock) Destroy() error {
+	return l.file.Close()
+}
+
+func NewLock(file string) (Lock, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return nil, err
+	}
+	l := &lock{int(f.Fd()), f}
+	return l, nil
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/perallocate_unsupported.go b/third_party/forked/etcd221/pkg/fileutil/perallocate_unsupported.go
new file mode 100644
index 0000000000000..c1a952bb79686
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/perallocate_unsupported.go
@@ -0,0 +1,28 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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.
+
+// +build !linux
+
+package fileutil
+
+import "os"
+
+// Preallocate tries to allocate the space for given
+// file. This operation is only supported on linux by a
+// few filesystems (btrfs, ext4, etc.).
+// If the operation is unsupported, no error will be returned.
+// Otherwise, the error encountered will be returned.
+func Preallocate(f *os.File, sizeInBytes int) error {
+	return nil
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/preallocate.go b/third_party/forked/etcd221/pkg/fileutil/preallocate.go
new file mode 100644
index 0000000000000..c4bd4f4c815ca
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/preallocate.go
@@ -0,0 +1,42 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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.
+
+// +build linux
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+// Preallocate tries to allocate the space for given
+// file. This operation is only supported on linux by a
+// few filesystems (btrfs, ext4, etc.).
+// If the operation is unsupported, no error will be returned.
+// Otherwise, the error encountered will be returned.
+func Preallocate(f *os.File, sizeInBytes int) error {
+	// use mode = 1 to keep size
+	// see FALLOC_FL_KEEP_SIZE
+	err := syscall.Fallocate(int(f.Fd()), 1, 0, int64(sizeInBytes))
+	if err != nil {
+		errno, ok := err.(syscall.Errno)
+		// treat not support as nil error
+		if ok && errno == syscall.ENOTSUP {
+			return nil
+		}
+		return err
+	}
+	return nil
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/preallocate_test.go b/third_party/forked/etcd221/pkg/fileutil/preallocate_test.go
new file mode 100644
index 0000000000000..d5f2a71f304b4
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/preallocate_test.go
@@ -0,0 +1,53 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 fileutil
+
+import (
+	"io/ioutil"
+	"os"
+	"runtime"
+	"testing"
+)
+
+func TestPreallocate(t *testing.T) {
+	if runtime.GOOS != "linux" {
+		t.Skipf("skip testPreallocate, OS = %s", runtime.GOOS)
+	}
+
+	p, err := ioutil.TempDir(os.TempDir(), "preallocateTest")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(p)
+
+	f, err := ioutil.TempFile(p, "")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	size := 64 * 1000
+	err = Preallocate(f, size)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	stat, err := f.Stat()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if stat.Size() != 0 {
+		t.Errorf("size = %d, want %d", stat.Size(), 0)
+	}
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/purge.go b/third_party/forked/etcd221/pkg/fileutil/purge.go
new file mode 100644
index 0000000000000..375aa97197446
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/purge.go
@@ -0,0 +1,80 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 fileutil
+
+import (
+	"os"
+	"path"
+	"sort"
+	"strings"
+	"time"
+)
+
+func PurgeFile(dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}) <-chan error {
+	errC := make(chan error, 1)
+	go func() {
+		for {
+			fnames, err := ReadDir(dirname)
+			if err != nil {
+				errC <- err
+				return
+			}
+			newfnames := make([]string, 0)
+			for _, fname := range fnames {
+				if strings.HasSuffix(fname, suffix) {
+					newfnames = append(newfnames, fname)
+				}
+			}
+			sort.Strings(newfnames)
+			for len(newfnames) > int(max) {
+				f := path.Join(dirname, newfnames[0])
+				l, err := NewLock(f)
+				if err != nil {
+					errC <- err
+					return
+				}
+				err = l.TryLock()
+				if err != nil {
+					break
+				}
+				err = os.Remove(f)
+				if err != nil {
+					errC <- err
+					return
+				}
+				err = l.Unlock()
+				if err != nil {
+					plog.Errorf("error unlocking %s when purging file (%v)", l.Name(), err)
+					errC <- err
+					return
+				}
+				err = l.Destroy()
+				if err != nil {
+					plog.Errorf("error destroying lock %s when purging file (%v)", l.Name(), err)
+					errC <- err
+					return
+				}
+				plog.Infof("purged file %s successfully", f)
+				newfnames = newfnames[1:]
+			}
+			select {
+			case <-time.After(interval):
+			case <-stop:
+				return
+			}
+		}
+	}()
+	return errC
+}
diff --git a/third_party/forked/etcd221/pkg/fileutil/purge_test.go b/third_party/forked/etcd221/pkg/fileutil/purge_test.go
new file mode 100644
index 0000000000000..0b11b23a579bf
--- /dev/null
+++ b/third_party/forked/etcd221/pkg/fileutil/purge_test.go
@@ -0,0 +1,132 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 fileutil
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"reflect"
+	"testing"
+	"time"
+)
+
+func TestPurgeFile(t *testing.T) {
+	dir, err := ioutil.TempDir("", "purgefile")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(dir)
+
+	for i := 0; i < 5; i++ {
+		_, err = os.Create(path.Join(dir, fmt.Sprintf("%d.test", i)))
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	stop := make(chan struct{})
+	errch := PurgeFile(dir, "test", 3, time.Millisecond, stop)
+	for i := 5; i < 10; i++ {
+		_, err = os.Create(path.Join(dir, fmt.Sprintf("%d.test", i)))
+		if err != nil {
+			t.Fatal(err)
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+	fnames, err := ReadDir(dir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	wnames := []string{"7.test", "8.test", "9.test"}
+	if !reflect.DeepEqual(fnames, wnames) {
+		t.Errorf("filenames = %v, want %v", fnames, wnames)
+	}
+	select {
+	case err := <-errch:
+		t.Errorf("unexpected purge error %v", err)
+	case <-time.After(time.Millisecond):
+	}
+	close(stop)
+}
+
+func TestPurgeFileHoldingLock(t *testing.T) {
+	dir, err := ioutil.TempDir("", "purgefile")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(dir)
+
+	for i := 0; i < 10; i++ {
+		_, err = os.Create(path.Join(dir, fmt.Sprintf("%d.test", i)))
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	// create a purge barrier at 5
+	l, err := NewLock(path.Join(dir, fmt.Sprintf("%d.test", 5)))
+	err = l.Lock()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	stop := make(chan struct{})
+	errch := PurgeFile(dir, "test", 3, time.Millisecond, stop)
+	time.Sleep(20 * time.Millisecond)
+
+	fnames, err := ReadDir(dir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	wnames := []string{"5.test", "6.test", "7.test", "8.test", "9.test"}
+	if !reflect.DeepEqual(fnames, wnames) {
+		t.Errorf("filenames = %v, want %v", fnames, wnames)
+	}
+	select {
+	case err := <-errch:
+		t.Errorf("unexpected purge error %v", err)
+	case <-time.After(time.Millisecond):
+	}
+
+	// remove the purge barrier
+	err = l.Unlock()
+	if err != nil {
+		t.Fatal(err)
+	}
+	err = l.Destroy()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	time.Sleep(20 * time.Millisecond)
+
+	fnames, err = ReadDir(dir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	wnames = []string{"7.test", "8.test", "9.test"}
+	if !reflect.DeepEqual(fnames, wnames) {
+		t.Errorf("filenames = %v, want %v", fnames, wnames)
+	}
+	select {
+	case err := <-errch:
+		t.Errorf("unexpected purge error %v", err)
+	case <-time.After(time.Millisecond):
+	}
+
+	close(stop)
+}
diff --git a/third_party/forked/etcd221/wal/BUILD b/third_party/forked/etcd221/wal/BUILD
new file mode 100644
index 0000000000000..797bc80cd03f8
--- /dev/null
+++ b/third_party/forked/etcd221/wal/BUILD
@@ -0,0 +1,49 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "decoder.go",
+        "doc.go",
+        "encoder.go",
+        "metrics.go",
+        "multi_readcloser.go",
+        "repair.go",
+        "util.go",
+        "wal.go",
+    ],
+    tags = ["automanaged"],
+    deps = [
+        "//third_party/forked/etcd221/pkg/fileutil:go_default_library",
+        "//vendor:github.com/coreos/etcd/pkg/crc",
+        "//vendor:github.com/coreos/etcd/pkg/pbutil",
+        "//vendor:github.com/coreos/etcd/raft",
+        "//vendor:github.com/coreos/etcd/raft/raftpb",
+        "//vendor:github.com/coreos/etcd/wal/walpb",
+        "//vendor:github.com/coreos/pkg/capnslog",
+        "//vendor:github.com/prometheus/client_golang/prometheus",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [
+        ":package-srcs",
+        "//third_party/forked/etcd221/wal/walpb:all-srcs",
+    ],
+    tags = ["automanaged"],
+)
diff --git a/third_party/forked/etcd221/wal/decoder.go b/third_party/forked/etcd221/wal/decoder.go
new file mode 100644
index 0000000000000..f75c919fba6e2
--- /dev/null
+++ b/third_party/forked/etcd221/wal/decoder.go
@@ -0,0 +1,103 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 wal
+
+import (
+	"bufio"
+	"encoding/binary"
+	"hash"
+	"io"
+	"sync"
+
+	"github.com/coreos/etcd/pkg/crc"
+	"github.com/coreos/etcd/pkg/pbutil"
+	"github.com/coreos/etcd/raft/raftpb"
+	"github.com/coreos/etcd/wal/walpb"
+)
+
+type decoder struct {
+	mu sync.Mutex
+	br *bufio.Reader
+
+	c   io.Closer
+	crc hash.Hash32
+}
+
+func newDecoder(rc io.ReadCloser) *decoder {
+	return &decoder{
+		br:  bufio.NewReader(rc),
+		c:   rc,
+		crc: crc.New(0, crcTable),
+	}
+}
+
+func (d *decoder) decode(rec *walpb.Record) error {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	rec.Reset()
+	l, err := readInt64(d.br)
+	if err != nil {
+		return err
+	}
+	data := make([]byte, l)
+	if _, err = io.ReadFull(d.br, data); err != nil {
+		// ReadFull returns io.EOF only if no bytes were read
+		// the decoder should treat this as an ErrUnexpectedEOF instead.
+		if err == io.EOF {
+			err = io.ErrUnexpectedEOF
+		}
+		return err
+	}
+	if err := rec.Unmarshal(data); err != nil {
+		return err
+	}
+	// skip crc checking if the record type is crcType
+	if rec.Type == crcType {
+		return nil
+	}
+	d.crc.Write(rec.Data)
+	return rec.Validate(d.crc.Sum32())
+}
+
+func (d *decoder) updateCRC(prevCrc uint32) {
+	d.crc = crc.New(prevCrc, crcTable)
+}
+
+func (d *decoder) lastCRC() uint32 {
+	return d.crc.Sum32()
+}
+
+func (d *decoder) close() error {
+	return d.c.Close()
+}
+
+func mustUnmarshalEntry(d []byte) raftpb.Entry {
+	var e raftpb.Entry
+	pbutil.MustUnmarshal(&e, d)
+	return e
+}
+
+func mustUnmarshalState(d []byte) raftpb.HardState {
+	var s raftpb.HardState
+	pbutil.MustUnmarshal(&s, d)
+	return s
+}
+
+func readInt64(r io.Reader) (int64, error) {
+	var n int64
+	err := binary.Read(r, binary.LittleEndian, &n)
+	return n, err
+}
diff --git a/third_party/forked/etcd221/wal/doc.go b/third_party/forked/etcd221/wal/doc.go
new file mode 100644
index 0000000000000..769b522f040b5
--- /dev/null
+++ b/third_party/forked/etcd221/wal/doc.go
@@ -0,0 +1,68 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 wal provides an implementation of a write ahead log that is used by
+etcd.
+
+A WAL is created at a particular directory and is made up of a number of
+segmented WAL files. Inside of each file the raft state and entries are appended
+to it with the Save method:
+
+	metadata := []byte{}
+	w, err := wal.Create("/var/lib/etcd", metadata)
+	...
+	err := w.Save(s, ents)
+
+After saving an raft snapshot to disk, SaveSnapshot method should be called to
+record it. So WAL can match with the saved snapshot when restarting.
+
+	err := w.SaveSnapshot(walpb.Snapshot{Index: 10, Term: 2})
+
+When a user has finished using a WAL it must be closed:
+
+	w.Close()
+
+WAL files are placed inside of the directory in the following format:
+$seq-$index.wal
+
+The first WAL file to be created will be 0000000000000000-0000000000000000.wal
+indicating an initial sequence of 0 and an initial raft index of 0. The first
+entry written to WAL MUST have raft index 0.
+
+WAL will cuts its current wal files if its size exceeds 8MB. This will increment an internal
+sequence number and cause a new file to be created. If the last raft index saved
+was 0x20 and this is the first time cut has been called on this WAL then the sequence will
+increment from 0x0 to 0x1. The new file will be: 0000000000000001-0000000000000021.wal.
+If a second cut issues 0x10 entries with incremental index later then the file will be called:
+0000000000000002-0000000000000031.wal.
+
+At a later time a WAL can be opened at a particular snapshot. If there is no
+snapshot, an empty snapshot should be passed in.
+
+	w, err := wal.Open("/var/lib/etcd", walpb.Snapshot{Index: 10, Term: 2})
+	...
+
+The snapshot must have been written to the WAL.
+
+Additional items cannot be Saved to this WAL until all of the items from the given
+snapshot to the end of the WAL are read first:
+
+	metadata, state, ents, err := w.ReadAll()
+
+This will give you the metadata, the last raft.State and the slice of
+raft.Entry items in the log.
+
+*/
+package wal
diff --git a/third_party/forked/etcd221/wal/encoder.go b/third_party/forked/etcd221/wal/encoder.go
new file mode 100644
index 0000000000000..959f90ad4d686
--- /dev/null
+++ b/third_party/forked/etcd221/wal/encoder.go
@@ -0,0 +1,89 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 wal
+
+import (
+	"bufio"
+	"encoding/binary"
+	"hash"
+	"io"
+	"sync"
+
+	"github.com/coreos/etcd/pkg/crc"
+	"github.com/coreos/etcd/wal/walpb"
+)
+
+type encoder struct {
+	mu sync.Mutex
+	bw *bufio.Writer
+
+	crc       hash.Hash32
+	buf       []byte
+	uint64buf []byte
+}
+
+func newEncoder(w io.Writer, prevCrc uint32) *encoder {
+	return &encoder{
+		bw:  bufio.NewWriter(w),
+		crc: crc.New(prevCrc, crcTable),
+		// 1MB buffer
+		buf:       make([]byte, 1024*1024),
+		uint64buf: make([]byte, 8),
+	}
+}
+
+func (e *encoder) encode(rec *walpb.Record) error {
+	e.mu.Lock()
+	defer e.mu.Unlock()
+
+	e.crc.Write(rec.Data)
+	rec.Crc = e.crc.Sum32()
+	var (
+		data []byte
+		err  error
+		n    int
+	)
+
+	if rec.Size() > len(e.buf) {
+		data, err = rec.Marshal()
+		if err != nil {
+			return err
+		}
+	} else {
+		n, err = rec.MarshalTo(e.buf)
+		if err != nil {
+			return err
+		}
+		data = e.buf[:n]
+	}
+	if err := writeInt64(e.bw, int64(len(data)), e.uint64buf); err != nil {
+		return err
+	}
+	_, err = e.bw.Write(data)
+	return err
+}
+
+func (e *encoder) flush() error {
+	e.mu.Lock()
+	defer e.mu.Unlock()
+	return e.bw.Flush()
+}
+
+func writeInt64(w io.Writer, n int64, buf []byte) error {
+	// http://golang.org/src/encoding/binary/binary.go
+	binary.LittleEndian.PutUint64(buf, uint64(n))
+	_, err := w.Write(buf)
+	return err
+}
diff --git a/third_party/forked/etcd221/wal/metrics.go b/third_party/forked/etcd221/wal/metrics.go
new file mode 100644
index 0000000000000..578ee91c86e40
--- /dev/null
+++ b/third_party/forked/etcd221/wal/metrics.go
@@ -0,0 +1,37 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 wal
+
+import "github.com/prometheus/client_golang/prometheus"
+
+var (
+	syncDurations = prometheus.NewSummary(prometheus.SummaryOpts{
+		Namespace: "etcd",
+		Subsystem: "wal",
+		Name:      "fsync_durations_microseconds",
+		Help:      "The latency distributions of fsync called by wal.",
+	})
+	lastIndexSaved = prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace: "etcd",
+		Subsystem: "wal",
+		Name:      "last_index_saved",
+		Help:      "The index of the last entry saved by wal.",
+	})
+)
+
+func init() {
+	prometheus.MustRegister(syncDurations)
+	prometheus.MustRegister(lastIndexSaved)
+}
diff --git a/third_party/forked/etcd221/wal/multi_readcloser.go b/third_party/forked/etcd221/wal/multi_readcloser.go
new file mode 100644
index 0000000000000..513c6d17d941b
--- /dev/null
+++ b/third_party/forked/etcd221/wal/multi_readcloser.go
@@ -0,0 +1,45 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 wal
+
+import "io"
+
+type multiReadCloser struct {
+	closers []io.Closer
+	reader  io.Reader
+}
+
+func (mc *multiReadCloser) Close() error {
+	var err error
+	for i := range mc.closers {
+		err = mc.closers[i].Close()
+	}
+	return err
+}
+
+func (mc *multiReadCloser) Read(p []byte) (int, error) {
+	return mc.reader.Read(p)
+}
+
+func MultiReadCloser(readClosers ...io.ReadCloser) io.ReadCloser {
+	cs := make([]io.Closer, len(readClosers))
+	rs := make([]io.Reader, len(readClosers))
+	for i := range readClosers {
+		cs[i] = readClosers[i]
+		rs[i] = readClosers[i]
+	}
+	r := io.MultiReader(rs...)
+	return &multiReadCloser{cs, r}
+}
diff --git a/third_party/forked/etcd221/wal/repair.go b/third_party/forked/etcd221/wal/repair.go
new file mode 100644
index 0000000000000..55d6bcfc7a868
--- /dev/null
+++ b/third_party/forked/etcd221/wal/repair.go
@@ -0,0 +1,107 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 wal
+
+import (
+	"io"
+	"os"
+	"path"
+
+	"k8s.io/kubernetes/third_party/forked/etcd221/pkg/fileutil"
+
+	"github.com/coreos/etcd/wal/walpb"
+)
+
+// Repair tries to repair the unexpectedEOF error in the
+// last wal file by truncating.
+func Repair(dirpath string) bool {
+	f, err := openLast(dirpath)
+	if err != nil {
+		return false
+	}
+	defer f.Close()
+
+	n := 0
+	rec := &walpb.Record{}
+
+	decoder := newDecoder(f)
+	defer decoder.close()
+	for {
+		err := decoder.decode(rec)
+		switch err {
+		case nil:
+			n += 8 + rec.Size()
+			// update crc of the decoder when necessary
+			switch rec.Type {
+			case crcType:
+				crc := decoder.crc.Sum32()
+				// current crc of decoder must match the crc of the record.
+				// do no need to match 0 crc, since the decoder is a new one at this case.
+				if crc != 0 && rec.Validate(crc) != nil {
+					return false
+				}
+				decoder.updateCRC(rec.Crc)
+			}
+			continue
+		case io.EOF:
+			return true
+		case io.ErrUnexpectedEOF:
+			plog.Noticef("repairing %v", f.Name())
+			bf, bferr := os.Create(f.Name() + ".broken")
+			if bferr != nil {
+				plog.Errorf("could not repair %v, failed to create backup file", f.Name())
+				return false
+			}
+			defer bf.Close()
+
+			if _, err = f.Seek(0, os.SEEK_SET); err != nil {
+				plog.Errorf("could not repair %v, failed to read file", f.Name())
+				return false
+			}
+
+			if _, err = io.Copy(bf, f); err != nil {
+				plog.Errorf("could not repair %v, failed to copy file", f.Name())
+				return false
+			}
+
+			if err = f.Truncate(int64(n)); err != nil {
+				plog.Errorf("could not repair %v, failed to truncate file", f.Name())
+				return false
+			}
+			if err = f.Sync(); err != nil {
+				plog.Errorf("could not repair %v, failed to sync file", f.Name())
+				return false
+			}
+			return true
+		default:
+			plog.Errorf("could not repair error (%v)", err)
+			return false
+		}
+	}
+}
+
+// openLast opens the last wal file for read and write.
+func openLast(dirpath string) (*os.File, error) {
+	names, err := fileutil.ReadDir(dirpath)
+	if err != nil {
+		return nil, err
+	}
+	names = checkWalNames(names)
+	if len(names) == 0 {
+		return nil, ErrFileNotFound
+	}
+	last := path.Join(dirpath, names[len(names)-1])
+	return os.OpenFile(last, os.O_RDWR, 0)
+}
diff --git a/third_party/forked/etcd221/wal/util.go b/third_party/forked/etcd221/wal/util.go
new file mode 100644
index 0000000000000..b40efc8b1220b
--- /dev/null
+++ b/third_party/forked/etcd221/wal/util.go
@@ -0,0 +1,93 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 wal
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"k8s.io/kubernetes/third_party/forked/etcd221/pkg/fileutil"
+)
+
+var (
+	badWalName = errors.New("bad wal name")
+)
+
+func Exist(dirpath string) bool {
+	names, err := fileutil.ReadDir(dirpath)
+	if err != nil {
+		return false
+	}
+	return len(names) != 0
+}
+
+// searchIndex returns the last array index of names whose raft index section is
+// equal to or smaller than the given index.
+// The given names MUST be sorted.
+func searchIndex(names []string, index uint64) (int, bool) {
+	for i := len(names) - 1; i >= 0; i-- {
+		name := names[i]
+		_, curIndex, err := parseWalName(name)
+		if err != nil {
+			plog.Panicf("parse correct name should never fail: %v", err)
+		}
+		if index >= curIndex {
+			return i, true
+		}
+	}
+	return -1, false
+}
+
+// names should have been sorted based on sequence number.
+// isValidSeq checks whether seq increases continuously.
+func isValidSeq(names []string) bool {
+	var lastSeq uint64
+	for _, name := range names {
+		curSeq, _, err := parseWalName(name)
+		if err != nil {
+			plog.Panicf("parse correct name should never fail: %v", err)
+		}
+		if lastSeq != 0 && lastSeq != curSeq-1 {
+			return false
+		}
+		lastSeq = curSeq
+	}
+	return true
+}
+
+func checkWalNames(names []string) []string {
+	wnames := make([]string, 0)
+	for _, name := range names {
+		if _, _, err := parseWalName(name); err != nil {
+			plog.Warningf("ignored file %v in wal", name)
+			continue
+		}
+		wnames = append(wnames, name)
+	}
+	return wnames
+}
+
+func parseWalName(str string) (seq, index uint64, err error) {
+	if !strings.HasSuffix(str, ".wal") {
+		return 0, 0, badWalName
+	}
+	_, err = fmt.Sscanf(str, "%016x-%016x.wal", &seq, &index)
+	return seq, index, err
+}
+
+func walName(seq, index uint64) string {
+	return fmt.Sprintf("%016x-%016x.wal", seq, index)
+}
diff --git a/third_party/forked/etcd221/wal/wal.go b/third_party/forked/etcd221/wal/wal.go
new file mode 100644
index 0000000000000..a39ef52b44ec6
--- /dev/null
+++ b/third_party/forked/etcd221/wal/wal.go
@@ -0,0 +1,548 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 wal
+
+import (
+	"errors"
+	"fmt"
+	"hash/crc32"
+	"io"
+	"os"
+	"path"
+	"reflect"
+	"sync"
+	"time"
+
+	"k8s.io/kubernetes/third_party/forked/etcd221/pkg/fileutil"
+
+	"github.com/coreos/etcd/pkg/pbutil"
+	"github.com/coreos/etcd/raft"
+	"github.com/coreos/etcd/raft/raftpb"
+	"github.com/coreos/etcd/wal/walpb"
+	"github.com/coreos/pkg/capnslog"
+)
+
+const (
+	metadataType int64 = iota + 1
+	entryType
+	stateType
+	crcType
+	snapshotType
+
+	// the owner can make/remove files inside the directory
+	privateDirMode = 0700
+
+	// the expected size of each wal segment file.
+	// the actual size might be bigger than it.
+	segmentSizeBytes = 64 * 1000 * 1000 // 64MB
+)
+
+var (
+	plog = capnslog.NewPackageLogger("github.com/coreos/etcd", "wal")
+
+	ErrMetadataConflict = errors.New("wal: conflicting metadata found")
+	ErrFileNotFound     = errors.New("wal: file not found")
+	ErrCRCMismatch      = errors.New("wal: crc mismatch")
+	ErrSnapshotMismatch = errors.New("wal: snapshot mismatch")
+	ErrSnapshotNotFound = errors.New("wal: snapshot not found")
+	crcTable            = crc32.MakeTable(crc32.Castagnoli)
+)
+
+// WAL is a logical repersentation of the stable storage.
+// WAL is either in read mode or append mode but not both.
+// A newly created WAL is in append mode, and ready for appending records.
+// A just opened WAL is in read mode, and ready for reading records.
+// The WAL will be ready for appending after reading out all the previous records.
+type WAL struct {
+	dir      string           // the living directory of the underlay files
+	metadata []byte           // metadata recorded at the head of each WAL
+	state    raftpb.HardState // hardstate recorded at the head of WAL
+
+	start   walpb.Snapshot // snapshot to start reading
+	decoder *decoder       // decoder to decode records
+
+	mu      sync.Mutex
+	f       *os.File // underlay file opened for appending, sync
+	seq     uint64   // sequence of the wal file currently used for writes
+	enti    uint64   // index of the last entry saved to the wal
+	encoder *encoder // encoder to encode records
+
+	locks []fileutil.Lock // the file locks the WAL is holding (the name is increasing)
+}
+
+// Create creates a WAL ready for appending records. The given metadata is
+// recorded at the head of each WAL file, and can be retrieved with ReadAll.
+func Create(dirpath string, metadata []byte) (*WAL, error) {
+	if Exist(dirpath) {
+		return nil, os.ErrExist
+	}
+
+	if err := os.MkdirAll(dirpath, privateDirMode); err != nil {
+		return nil, err
+	}
+
+	p := path.Join(dirpath, walName(0, 0))
+	f, err := os.OpenFile(p, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0600)
+	if err != nil {
+		return nil, err
+	}
+	l, err := fileutil.NewLock(f.Name())
+	if err != nil {
+		return nil, err
+	}
+	err = l.Lock()
+	if err != nil {
+		return nil, err
+	}
+
+	w := &WAL{
+		dir:      dirpath,
+		metadata: metadata,
+		seq:      0,
+		f:        f,
+		encoder:  newEncoder(f, 0),
+	}
+	w.locks = append(w.locks, l)
+	if err := w.saveCrc(0); err != nil {
+		return nil, err
+	}
+	if err := w.encoder.encode(&walpb.Record{Type: metadataType, Data: metadata}); err != nil {
+		return nil, err
+	}
+	if err = w.SaveSnapshot(walpb.Snapshot{}); err != nil {
+		return nil, err
+	}
+	return w, nil
+}
+
+// Open opens the WAL at the given snap.
+// The snap SHOULD have been previously saved to the WAL, or the following
+// ReadAll will fail.
+// The returned WAL is ready to read and the first record will be the one after
+// the given snap. The WAL cannot be appended to before reading out all of its
+// previous records.
+func Open(dirpath string, snap walpb.Snapshot) (*WAL, error) {
+	return openAtIndex(dirpath, snap, true)
+}
+
+// OpenForRead only opens the wal files for read.
+// Write on a read only wal panics.
+func OpenForRead(dirpath string, snap walpb.Snapshot) (*WAL, error) {
+	return openAtIndex(dirpath, snap, false)
+}
+
+func openAtIndex(dirpath string, snap walpb.Snapshot, write bool) (*WAL, error) {
+	names, err := fileutil.ReadDir(dirpath)
+	if err != nil {
+		return nil, err
+	}
+	names = checkWalNames(names)
+	if len(names) == 0 {
+		return nil, ErrFileNotFound
+	}
+
+	nameIndex, ok := searchIndex(names, snap.Index)
+	if !ok || !isValidSeq(names[nameIndex:]) {
+		return nil, ErrFileNotFound
+	}
+
+	// open the wal files for reading
+	rcs := make([]io.ReadCloser, 0)
+	ls := make([]fileutil.Lock, 0)
+	for _, name := range names[nameIndex:] {
+		f, err := os.Open(path.Join(dirpath, name))
+		if err != nil {
+			return nil, err
+		}
+		l, err := fileutil.NewLock(f.Name())
+		if err != nil {
+			return nil, err
+		}
+		err = l.TryLock()
+		if err != nil {
+			if write {
+				return nil, err
+			}
+		}
+		rcs = append(rcs, f)
+		ls = append(ls, l)
+	}
+	rc := MultiReadCloser(rcs...)
+
+	// create a WAL ready for reading
+	w := &WAL{
+		dir:     dirpath,
+		start:   snap,
+		decoder: newDecoder(rc),
+		locks:   ls,
+	}
+
+	if write {
+		// open the lastest wal file for appending
+		seq, _, err := parseWalName(names[len(names)-1])
+		if err != nil {
+			rc.Close()
+			return nil, err
+		}
+		last := path.Join(dirpath, names[len(names)-1])
+
+		f, err := os.OpenFile(last, os.O_WRONLY|os.O_APPEND, 0)
+		if err != nil {
+			rc.Close()
+			return nil, err
+		}
+		err = fileutil.Preallocate(f, segmentSizeBytes)
+		if err != nil {
+			rc.Close()
+			plog.Errorf("failed to allocate space when creating new wal file (%v)", err)
+			return nil, err
+		}
+
+		w.f = f
+		w.seq = seq
+	}
+
+	return w, nil
+}
+
+// ReadAll reads out records of the current WAL.
+// If opened in write mode, it must read out all records until EOF. Or an error
+// will be returned.
+// If opened in read mode, it will try to read all records if possible.
+// If it cannot read out the expected snap, it will return ErrSnapshotNotFound.
+// If loaded snap doesn't match with the expected one, it will return
+// all the records and error ErrSnapshotMismatch.
+// TODO: detect not-last-snap error.
+// TODO: maybe loose the checking of match.
+// After ReadAll, the WAL will be ready for appending new records.
+func (w *WAL) ReadAll() (metadata []byte, state raftpb.HardState, ents []raftpb.Entry, err error) {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	rec := &walpb.Record{}
+	decoder := w.decoder
+
+	var match bool
+	for err = decoder.decode(rec); err == nil; err = decoder.decode(rec) {
+		switch rec.Type {
+		case entryType:
+			e := mustUnmarshalEntry(rec.Data)
+			if e.Index > w.start.Index {
+				ents = append(ents[:e.Index-w.start.Index-1], e)
+			}
+			w.enti = e.Index
+		case stateType:
+			state = mustUnmarshalState(rec.Data)
+		case metadataType:
+			if metadata != nil && !reflect.DeepEqual(metadata, rec.Data) {
+				state.Reset()
+				return nil, state, nil, ErrMetadataConflict
+			}
+			metadata = rec.Data
+		case crcType:
+			crc := decoder.crc.Sum32()
+			// current crc of decoder must match the crc of the record.
+			// do no need to match 0 crc, since the decoder is a new one at this case.
+			if crc != 0 && rec.Validate(crc) != nil {
+				state.Reset()
+				return nil, state, nil, ErrCRCMismatch
+			}
+			decoder.updateCRC(rec.Crc)
+		case snapshotType:
+			var snap walpb.Snapshot
+			pbutil.MustUnmarshal(&snap, rec.Data)
+			if snap.Index == w.start.Index {
+				if snap.Term != w.start.Term {
+					state.Reset()
+					return nil, state, nil, ErrSnapshotMismatch
+				}
+				match = true
+			}
+		default:
+			state.Reset()
+			return nil, state, nil, fmt.Errorf("unexpected block type %d", rec.Type)
+		}
+	}
+
+	switch w.f {
+	case nil:
+		// We do not have to read out all entries in read mode.
+		// The last record maybe a partial written one, so
+		// ErrunexpectedEOF might be returned.
+		if err != io.EOF && err != io.ErrUnexpectedEOF {
+			state.Reset()
+			return nil, state, nil, err
+		}
+	default:
+		// We must read all of the entries if WAL is opened in write mode.
+		if err != io.EOF {
+			state.Reset()
+			return nil, state, nil, err
+		}
+	}
+
+	err = nil
+	if !match {
+		err = ErrSnapshotNotFound
+	}
+
+	// close decoder, disable reading
+	w.decoder.close()
+	w.start = walpb.Snapshot{}
+
+	w.metadata = metadata
+
+	if w.f != nil {
+		// create encoder (chain crc with the decoder), enable appending
+		w.encoder = newEncoder(w.f, w.decoder.lastCRC())
+		w.decoder = nil
+		lastIndexSaved.Set(float64(w.enti))
+	}
+
+	return metadata, state, ents, err
+}
+
+// cut closes current file written and creates a new one ready to append.
+// cut first creates a temp wal file and writes necessary headers into it.
+// Then cut atomtically rename temp wal file to a wal file.
+func (w *WAL) cut() error {
+	// close old wal file
+	if err := w.sync(); err != nil {
+		return err
+	}
+	if err := w.f.Close(); err != nil {
+		return err
+	}
+
+	fpath := path.Join(w.dir, walName(w.seq+1, w.enti+1))
+	ftpath := fpath + ".tmp"
+
+	// create a temp wal file with name sequence + 1, or tuncate the existing one
+	ft, err := os.OpenFile(ftpath, os.O_WRONLY|os.O_APPEND|os.O_CREATE|os.O_TRUNC, 0600)
+	if err != nil {
+		return err
+	}
+
+	// update writer and save the previous crc
+	w.f = ft
+	prevCrc := w.encoder.crc.Sum32()
+	w.encoder = newEncoder(w.f, prevCrc)
+	if err := w.saveCrc(prevCrc); err != nil {
+		return err
+	}
+	if err := w.encoder.encode(&walpb.Record{Type: metadataType, Data: w.metadata}); err != nil {
+		return err
+	}
+	if err := w.saveState(&w.state); err != nil {
+		return err
+	}
+	// close temp wal file
+	if err := w.sync(); err != nil {
+		return err
+	}
+	if err := w.f.Close(); err != nil {
+		return err
+	}
+
+	// atomically move temp wal file to wal file
+	if err := os.Rename(ftpath, fpath); err != nil {
+		return err
+	}
+
+	// open the wal file and update writer again
+	f, err := os.OpenFile(fpath, os.O_WRONLY|os.O_APPEND, 0600)
+	if err != nil {
+		return err
+	}
+	err = fileutil.Preallocate(f, segmentSizeBytes)
+	if err != nil {
+		plog.Errorf("failed to allocate space when creating new wal file (%v)", err)
+		return err
+	}
+
+	w.f = f
+	prevCrc = w.encoder.crc.Sum32()
+	w.encoder = newEncoder(w.f, prevCrc)
+
+	// lock the new wal file
+	l, err := fileutil.NewLock(f.Name())
+	if err != nil {
+		return err
+	}
+
+	err = l.Lock()
+	if err != nil {
+		return err
+	}
+	w.locks = append(w.locks, l)
+
+	// increase the wal seq
+	w.seq++
+
+	plog.Infof("segmented wal file %v is created", fpath)
+	return nil
+}
+
+func (w *WAL) sync() error {
+	if w.encoder != nil {
+		if err := w.encoder.flush(); err != nil {
+			return err
+		}
+	}
+	start := time.Now()
+	err := w.f.Sync()
+	syncDurations.Observe(float64(time.Since(start).Nanoseconds() / int64(time.Microsecond)))
+	return err
+}
+
+// ReleaseLockTo releases the locks, which has smaller index than the given index
+// except the largest one among them.
+// For example, if WAL is holding lock 1,2,3,4,5,6, ReleaseLockTo(4) will release
+// lock 1,2 but keep 3. ReleaseLockTo(5) will release 1,2,3 but keep 4.
+func (w *WAL) ReleaseLockTo(index uint64) error {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	var smaller int
+	found := false
+
+	for i, l := range w.locks {
+		_, lockIndex, err := parseWalName(path.Base(l.Name()))
+		if err != nil {
+			return err
+		}
+		if lockIndex >= index {
+			smaller = i - 1
+			found = true
+			break
+		}
+	}
+
+	// if no lock index is greater than the release index, we can
+	// release lock upto the last one(excluding).
+	if !found && len(w.locks) != 0 {
+		smaller = len(w.locks) - 1
+	}
+
+	if smaller <= 0 {
+		return nil
+	}
+
+	for i := 0; i < smaller; i++ {
+		w.locks[i].Unlock()
+		w.locks[i].Destroy()
+	}
+	w.locks = w.locks[smaller:]
+
+	return nil
+}
+
+func (w *WAL) Close() error {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	if w.f != nil {
+		if err := w.sync(); err != nil {
+			return err
+		}
+		if err := w.f.Close(); err != nil {
+			return err
+		}
+	}
+	for _, l := range w.locks {
+		err := l.Unlock()
+		if err != nil {
+			plog.Errorf("failed to unlock during closing wal: %s", err)
+		}
+		err = l.Destroy()
+		if err != nil {
+			plog.Errorf("failed to destroy lock during closing wal: %s", err)
+		}
+	}
+	return nil
+}
+
+func (w *WAL) saveEntry(e *raftpb.Entry) error {
+	// TODO: add MustMarshalTo to reduce one allocation.
+	b := pbutil.MustMarshal(e)
+	rec := &walpb.Record{Type: entryType, Data: b}
+	if err := w.encoder.encode(rec); err != nil {
+		return err
+	}
+	w.enti = e.Index
+	lastIndexSaved.Set(float64(w.enti))
+	return nil
+}
+
+func (w *WAL) saveState(s *raftpb.HardState) error {
+	if raft.IsEmptyHardState(*s) {
+		return nil
+	}
+	w.state = *s
+	b := pbutil.MustMarshal(s)
+	rec := &walpb.Record{Type: stateType, Data: b}
+	return w.encoder.encode(rec)
+}
+
+func (w *WAL) Save(st raftpb.HardState, ents []raftpb.Entry) error {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	// short cut, do not call sync
+	if raft.IsEmptyHardState(st) && len(ents) == 0 {
+		return nil
+	}
+
+	// TODO(xiangli): no more reference operator
+	for i := range ents {
+		if err := w.saveEntry(&ents[i]); err != nil {
+			return err
+		}
+	}
+	if err := w.saveState(&st); err != nil {
+		return err
+	}
+
+	fstat, err := w.f.Stat()
+	if err != nil {
+		return err
+	}
+	if fstat.Size() < segmentSizeBytes {
+		return w.sync()
+	}
+	// TODO: add a test for this code path when refactoring the tests
+	return w.cut()
+}
+
+func (w *WAL) SaveSnapshot(e walpb.Snapshot) error {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	b := pbutil.MustMarshal(&e)
+	rec := &walpb.Record{Type: snapshotType, Data: b}
+	if err := w.encoder.encode(rec); err != nil {
+		return err
+	}
+	// update enti only when snapshot is ahead of last index
+	if w.enti < e.Index {
+		w.enti = e.Index
+	}
+	lastIndexSaved.Set(float64(w.enti))
+	return w.sync()
+}
+
+func (w *WAL) saveCrc(prevCrc uint32) error {
+	return w.encoder.encode(&walpb.Record{Type: crcType, Crc: prevCrc})
+}
diff --git a/third_party/forked/etcd221/wal/walpb/BUILD b/third_party/forked/etcd221/wal/walpb/BUILD
new file mode 100644
index 0000000000000..29def44028e44
--- /dev/null
+++ b/third_party/forked/etcd221/wal/walpb/BUILD
@@ -0,0 +1,31 @@
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "record.go",
+        "record.pb.go",
+    ],
+    tags = ["automanaged"],
+    deps = ["//vendor:github.com/gogo/protobuf/proto"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+)
diff --git a/third_party/forked/etcd221/wal/walpb/record.go b/third_party/forked/etcd221/wal/walpb/record.go
new file mode 100644
index 0000000000000..bb5368569761c
--- /dev/null
+++ b/third_party/forked/etcd221/wal/walpb/record.go
@@ -0,0 +1,29 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// 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 walpb
+
+import "errors"
+
+var (
+	ErrCRCMismatch = errors.New("walpb: crc mismatch")
+)
+
+func (rec *Record) Validate(crc uint32) error {
+	if rec.Crc == crc {
+		return nil
+	}
+	rec.Reset()
+	return ErrCRCMismatch
+}
diff --git a/third_party/forked/etcd221/wal/walpb/record.pb.go b/third_party/forked/etcd221/wal/walpb/record.pb.go
new file mode 100644
index 0000000000000..a9b38a47ef9be
--- /dev/null
+++ b/third_party/forked/etcd221/wal/walpb/record.pb.go
@@ -0,0 +1,447 @@
+// Code generated by protoc-gen-gogo.
+// source: record.proto
+// DO NOT EDIT!
+
+/*
+	Package walpb is a generated protocol buffer package.
+
+	It is generated from these files:
+		record.proto
+
+	It has these top-level messages:
+		Record
+		Snapshot
+*/
+package walpb
+
+import proto "github.com/gogo/protobuf/proto"
+import math "math"
+
+// discarding unused import gogoproto "github.com/coreos/etcd/Godeps/_workspace/src/gogoproto"
+
+import io "io"
+import fmt "fmt"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = math.Inf
+
+type Record struct {
+	Type             int64  `protobuf:"varint,1,opt,name=type" json:"type"`
+	Crc              uint32 `protobuf:"varint,2,opt,name=crc" json:"crc"`
+	Data             []byte `protobuf:"bytes,3,opt,name=data" json:"data,omitempty"`
+	XXX_unrecognized []byte `json:"-"`
+}
+
+func (m *Record) Reset()         { *m = Record{} }
+func (m *Record) String() string { return proto.CompactTextString(m) }
+func (*Record) ProtoMessage()    {}
+
+type Snapshot struct {
+	Index            uint64 `protobuf:"varint,1,opt,name=index" json:"index"`
+	Term             uint64 `protobuf:"varint,2,opt,name=term" json:"term"`
+	XXX_unrecognized []byte `json:"-"`
+}
+
+func (m *Snapshot) Reset()         { *m = Snapshot{} }
+func (m *Snapshot) String() string { return proto.CompactTextString(m) }
+func (*Snapshot) ProtoMessage()    {}
+
+func (m *Record) Marshal() (data []byte, err error) {
+	size := m.Size()
+	data = make([]byte, size)
+	n, err := m.MarshalTo(data)
+	if err != nil {
+		return nil, err
+	}
+	return data[:n], nil
+}
+
+func (m *Record) MarshalTo(data []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	data[i] = 0x8
+	i++
+	i = encodeVarintRecord(data, i, uint64(m.Type))
+	data[i] = 0x10
+	i++
+	i = encodeVarintRecord(data, i, uint64(m.Crc))
+	if m.Data != nil {
+		data[i] = 0x1a
+		i++
+		i = encodeVarintRecord(data, i, uint64(len(m.Data)))
+		i += copy(data[i:], m.Data)
+	}
+	if m.XXX_unrecognized != nil {
+		i += copy(data[i:], m.XXX_unrecognized)
+	}
+	return i, nil
+}
+
+func (m *Snapshot) Marshal() (data []byte, err error) {
+	size := m.Size()
+	data = make([]byte, size)
+	n, err := m.MarshalTo(data)
+	if err != nil {
+		return nil, err
+	}
+	return data[:n], nil
+}
+
+func (m *Snapshot) MarshalTo(data []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	data[i] = 0x8
+	i++
+	i = encodeVarintRecord(data, i, uint64(m.Index))
+	data[i] = 0x10
+	i++
+	i = encodeVarintRecord(data, i, uint64(m.Term))
+	if m.XXX_unrecognized != nil {
+		i += copy(data[i:], m.XXX_unrecognized)
+	}
+	return i, nil
+}
+
+func encodeFixed64Record(data []byte, offset int, v uint64) int {
+	data[offset] = uint8(v)
+	data[offset+1] = uint8(v >> 8)
+	data[offset+2] = uint8(v >> 16)
+	data[offset+3] = uint8(v >> 24)
+	data[offset+4] = uint8(v >> 32)
+	data[offset+5] = uint8(v >> 40)
+	data[offset+6] = uint8(v >> 48)
+	data[offset+7] = uint8(v >> 56)
+	return offset + 8
+}
+func encodeFixed32Record(data []byte, offset int, v uint32) int {
+	data[offset] = uint8(v)
+	data[offset+1] = uint8(v >> 8)
+	data[offset+2] = uint8(v >> 16)
+	data[offset+3] = uint8(v >> 24)
+	return offset + 4
+}
+func encodeVarintRecord(data []byte, offset int, v uint64) int {
+	for v >= 1<<7 {
+		data[offset] = uint8(v&0x7f | 0x80)
+		v >>= 7
+		offset++
+	}
+	data[offset] = uint8(v)
+	return offset + 1
+}
+func (m *Record) Size() (n int) {
+	var l int
+	_ = l
+	n += 1 + sovRecord(uint64(m.Type))
+	n += 1 + sovRecord(uint64(m.Crc))
+	if m.Data != nil {
+		l = len(m.Data)
+		n += 1 + l + sovRecord(uint64(l))
+	}
+	if m.XXX_unrecognized != nil {
+		n += len(m.XXX_unrecognized)
+	}
+	return n
+}
+
+func (m *Snapshot) Size() (n int) {
+	var l int
+	_ = l
+	n += 1 + sovRecord(uint64(m.Index))
+	n += 1 + sovRecord(uint64(m.Term))
+	if m.XXX_unrecognized != nil {
+		n += len(m.XXX_unrecognized)
+	}
+	return n
+}
+
+func sovRecord(x uint64) (n int) {
+	for {
+		n++
+		x >>= 7
+		if x == 0 {
+			break
+		}
+	}
+	return n
+}
+func sozRecord(x uint64) (n int) {
+	return sovRecord(uint64((x << 1) ^ uint64((int64(x) >> 63))))
+}
+func (m *Record) Unmarshal(data []byte) error {
+	l := len(data)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := data[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		switch fieldNum {
+		case 1:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Type", wireType)
+			}
+			m.Type = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.Type |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 2:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Crc", wireType)
+			}
+			m.Crc = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.Crc |= (uint32(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 3:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Data", wireType)
+			}
+			var byteLen int
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				byteLen |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if byteLen < 0 {
+				return ErrInvalidLengthRecord
+			}
+			postIndex := iNdEx + byteLen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.Data = append([]byte{}, data[iNdEx:postIndex]...)
+			iNdEx = postIndex
+		default:
+			var sizeOfWire int
+			for {
+				sizeOfWire++
+				wire >>= 7
+				if wire == 0 {
+					break
+				}
+			}
+			iNdEx -= sizeOfWire
+			skippy, err := skipRecord(data[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRecord
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.XXX_unrecognized = append(m.XXX_unrecognized, data[iNdEx:iNdEx+skippy]...)
+			iNdEx += skippy
+		}
+	}
+
+	return nil
+}
+func (m *Snapshot) Unmarshal(data []byte) error {
+	l := len(data)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := data[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		switch fieldNum {
+		case 1:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Index", wireType)
+			}
+			m.Index = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.Index |= (uint64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 2:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Term", wireType)
+			}
+			m.Term = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.Term |= (uint64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			var sizeOfWire int
+			for {
+				sizeOfWire++
+				wire >>= 7
+				if wire == 0 {
+					break
+				}
+			}
+			iNdEx -= sizeOfWire
+			skippy, err := skipRecord(data[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRecord
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.XXX_unrecognized = append(m.XXX_unrecognized, data[iNdEx:iNdEx+skippy]...)
+			iNdEx += skippy
+		}
+	}
+
+	return nil
+}
+func skipRecord(data []byte) (n int, err error) {
+	l := len(data)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if iNdEx >= l {
+				return 0, io.ErrUnexpectedEOF
+			}
+			b := data[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		wireType := int(wire & 0x7)
+		switch wireType {
+		case 0:
+			for {
+				if iNdEx >= l {
+					return 0, io.ErrUnexpectedEOF
+				}
+				iNdEx++
+				if data[iNdEx-1] < 0x80 {
+					break
+				}
+			}
+			return iNdEx, nil
+		case 1:
+			iNdEx += 8
+			return iNdEx, nil
+		case 2:
+			var length int
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return 0, io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				length |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			iNdEx += length
+			if length < 0 {
+				return 0, ErrInvalidLengthRecord
+			}
+			return iNdEx, nil
+		case 3:
+			for {
+				var innerWire uint64
+				var start int = iNdEx
+				for shift := uint(0); ; shift += 7 {
+					if iNdEx >= l {
+						return 0, io.ErrUnexpectedEOF
+					}
+					b := data[iNdEx]
+					iNdEx++
+					innerWire |= (uint64(b) & 0x7F) << shift
+					if b < 0x80 {
+						break
+					}
+				}
+				innerWireType := int(innerWire & 0x7)
+				if innerWireType == 4 {
+					break
+				}
+				next, err := skipRecord(data[start:])
+				if err != nil {
+					return 0, err
+				}
+				iNdEx = start + next
+			}
+			return iNdEx, nil
+		case 4:
+			return iNdEx, nil
+		case 5:
+			iNdEx += 4
+			return iNdEx, nil
+		default:
+			return 0, fmt.Errorf("proto: illegal wireType %d", wireType)
+		}
+	}
+	panic("unreachable")
+}
+
+var (
+	ErrInvalidLengthRecord = fmt.Errorf("proto: negative length found during unmarshaling")
+)
diff --git a/third_party/forked/etcd221/wal/walpb/record.proto b/third_party/forked/etcd221/wal/walpb/record.proto
new file mode 100644
index 0000000000000..b694cb2338aaf
--- /dev/null
+++ b/third_party/forked/etcd221/wal/walpb/record.proto
@@ -0,0 +1,20 @@
+syntax = "proto2";
+package walpb;
+
+import "gogoproto/gogo.proto";
+
+option (gogoproto.marshaler_all) = true;
+option (gogoproto.sizer_all) = true;
+option (gogoproto.unmarshaler_all) = true;
+option (gogoproto.goproto_getters_all) = false;
+
+message Record {
+	optional int64 type  = 1 [(gogoproto.nullable) = false];
+	optional uint32 crc  = 2 [(gogoproto.nullable) = false];
+	optional bytes data  = 3;
+}
+
+message Snapshot {
+	optional uint64 index = 1 [(gogoproto.nullable) = false];
+	optional uint64 term  = 2 [(gogoproto.nullable) = false];
+}