Remove support for etcd2 from cluster/images/etcd image

Removes etcd2 code and images.
Etcd2 is no longer supported as of 1.13, so rollback and management
tools for etcd2 should not be shipped any longer. If it is still desired
the older versions of the image can be used.

Change-Id: I516c40067f0a57c42d2a6ab4612071c5e556a005

cluster/images/etcd/Makefile

@@ -15,7 +15,7 @@
 # Build the etcd image
 #
 # Usage:
-# 	[BUNDLED_ETCD_VERSIONS=2.2.1 2.3.7 3.0.17 3.1.12 3.2.24 3.3.10] [REGISTRY=k8s.gcr.io] [ARCH=amd64] [BASEIMAGE=busybox] make (build|push)
+# 	[BUNDLED_ETCD_VERSIONS=3.0.17 3.1.12 3.2.24 3.3.10] [REGISTRY=k8s.gcr.io] [ARCH=amd64] [BASEIMAGE=busybox] make (build|push)
 #
 # The image contains different etcd versions to simplify
 # upgrades. Thus be careful when removing any versions from here.
@@ -26,7 +26,7 @@
 # Except from etcd-$(version) and etcdctl-$(version) binaries, we also
 # need etcd and etcdctl binaries for backward compatibility reasons.
 # That binary will be set to the last version from $(BUNDLED_ETCD_VERSIONS).
-BUNDLED_ETCD_VERSIONS?=2.2.1 2.3.7 3.0.17 3.1.12 3.2.24 3.3.10
+BUNDLED_ETCD_VERSIONS?=3.0.17 3.1.12 3.2.24 3.3.10
 
 # LATEST_ETCD_VERSION identifies the most recent etcd version available.
 LATEST_ETCD_VERSION?=3.3.10

cluster/images/etcd/README.md

@@ -34,7 +34,7 @@ version.
 Upgrades to any target version are supported. The data will be automatically upgraded
 in steps to each minor version until the target version is reached.
 
-Downgrades to the previous minor version of the 3.x series and from 3.0 to 2.3.7 are supported.
+Downgrades to the previous minor version of the 3.x series is supported.
 
 #### Permissions
 

cluster/images/etcd/migrate-if-needed.sh

@@ -17,17 +17,15 @@
 # NOTES
 # This script performs etcd upgrade based on the following environmental
 # variables:
-# TARGET_STORAGE - API of etcd to be used (supported: 'etcd2', 'etcd3')
-# TARGET_VERSION - etcd release to be used (supported: '2.2.1', '2.3.7', '3.0.17', '3.1.12', '3.2.24', "3.3.10")
+# TARGET_STORAGE - API of etcd to be used (supported: 'etcd3')
+# TARGET_VERSION - etcd release to be used (supported: '3.0.17', '3.1.12', '3.2.24', "3.3.10")
 # DATA_DIRECTORY - directory with etcd data
 #
 # The current etcd version and storage format is detected based on the
 # contents of "${DATA_DIRECTORY}/version.txt" file (if the file doesn't
-# exist, we default it to "2.2.1/etcd2".
+# exist, we default it to "3.0.17/etcd2".
 #
 # The update workflow support the following upgrade steps:
-# - 2.2.1/etcd2 -> 2.3.7/etcd2
-# - 2.3.7/etcd2 -> 3.0.17/etcd2
 # - 3.0.17/etcd3 -> 3.1.12/etcd3
 # - 3.1.12/etcd3 -> 3.2.24/etcd3
 # - 3.2.24/etcd3 -> 3.3.10/etcd3
@@ -43,7 +41,7 @@ set -o nounset
 
 # NOTE: BUNDLED_VERSION has to match release binaries present in the
 # etcd image (to make this script work correctly).
-BUNDLED_VERSIONS="2.2.1, 2.3.7, 3.0.17, 3.1.12, 3.2.24, 3.3.10"
+BUNDLED_VERSIONS="3.0.17, 3.1.12, 3.2.24, 3.3.10"
 
 ETCD_NAME="${ETCD_NAME:-etcd-$(hostname)}"
 if [ -z "${DATA_DIRECTORY:-}" ]; then

cluster/images/etcd/migrate/BUILD

@@ -20,28 +20,13 @@ go_library(
         "migrate_client.go",
         "migrate_server.go",
         "migrator.go",
-        "rollback_v2.go",
         "versions.go",
     ],
     importpath = "k8s.io/kubernetes/cluster/images/etcd/migrate",
     deps = [
-        "//third_party/forked/etcd221/wal:go_default_library",
         "//vendor/github.com/blang/semver:go_default_library",
         "//vendor/github.com/coreos/etcd/client:go_default_library",
         "//vendor/github.com/coreos/etcd/clientv3:go_default_library",
-        "//vendor/github.com/coreos/etcd/etcdserver:go_default_library",
-        "//vendor/github.com/coreos/etcd/etcdserver/etcdserverpb:go_default_library",
-        "//vendor/github.com/coreos/etcd/etcdserver/membership:go_default_library",
-        "//vendor/github.com/coreos/etcd/mvcc/backend:go_default_library",
-        "//vendor/github.com/coreos/etcd/mvcc/mvccpb:go_default_library",
-        "//vendor/github.com/coreos/etcd/pkg/pbutil:go_default_library",
-        "//vendor/github.com/coreos/etcd/pkg/types:go_default_library",
-        "//vendor/github.com/coreos/etcd/raft/raftpb:go_default_library",
-        "//vendor/github.com/coreos/etcd/snap:go_default_library",
-        "//vendor/github.com/coreos/etcd/store:go_default_library",
-        "//vendor/github.com/coreos/etcd/wal:go_default_library",
-        "//vendor/github.com/coreos/etcd/wal/walpb:go_default_library",
-        "//vendor/github.com/coreos/go-semver/semver:go_default_library",
         "//vendor/github.com/spf13/cobra:go_default_library",
         "//vendor/k8s.io/klog:go_default_library",
     ],

cluster/images/etcd/migrate/integration_test.go

@@ -40,8 +40,7 @@ import (
 )
 
 var (
-	testSupportedVersions = MustParseSupportedVersions("2.2.1, 2.3.7, 3.0.17, 3.1.12")
-	testVersionOldest     = &EtcdVersion{semver.MustParse("2.2.1")}
+	testSupportedVersions = MustParseSupportedVersions("3.0.17, 3.1.12")
 	testVersionPrevious   = &EtcdVersion{semver.MustParse("3.0.17")}
 	testVersionLatest     = &EtcdVersion{semver.MustParse("3.1.12")}
 )
@@ -55,15 +54,13 @@ func TestMigrate(t *testing.T) {
 		protocol     string
 	}{
 		// upgrades
-		{"v2-v3-up", 1, "2.2.1/etcd2", "3.0.17/etcd3", "https"},
 		{"v3-v3-up", 1, "3.0.17/etcd3", "3.1.12/etcd3", "https"},
-		{"oldest-newest-up", 1, "2.2.1/etcd2", "3.1.12/etcd3", "https"},
+		{"oldest-newest-up", 1, "3.0.17/etcd3", "3.1.12/etcd3", "https"},
 
 		// warning: v2->v3 ha upgrades not currently supported.
 		{"ha-v3-v3-up", 3, "3.0.17/etcd3", "3.1.12/etcd3", "https"},
 
 		// downgrades
-		{"v3-v2-down", 1, "3.0.17/etcd3", "2.2.1/etcd2", "https"},
 		{"v3-v3-down", 1, "3.1.12/etcd3", "3.0.17/etcd3", "https"},
 
 		// warning: ha downgrades not yet supported.

cluster/images/etcd/migrate/migrator.go

@@ -95,11 +95,9 @@ func (m *Migrator) MigrateIfNeeded(target *EtcdVersionPair) error {
 			}
 			return nil
 		case current.storageVersion == storageEtcd2 && target.storageVersion == storageEtcd3:
-			klog.Info("upgrading from etcd2 storage to etcd3 storage")
-			current, err = m.etcd2ToEtcd3Upgrade(current, target)
+			return fmt.Errorf("upgrading from etcd2 storage to etcd3 storage is not supported")
 		case current.version.Major == 3 && target.version.Major == 2:
-			klog.Info("downgrading from etcd 3.x to 2.x")
-			current, err = m.rollbackToEtcd2(current, target)
+			return fmt.Errorf("downgrading from etcd 3.x to 2.x is not supported")
 		case current.version.Major == target.version.Major && current.version.Minor < target.version.Minor:
 			stepVersion := m.cfg.supportedVersions.NextVersionPair(current)
 			klog.Infof("upgrading etcd from %s to %s", current, stepVersion)
@@ -114,18 +112,6 @@ func (m *Migrator) MigrateIfNeeded(target *EtcdVersionPair) error {
 	}
 }
 
-func (m *Migrator) backupEtcd2(current *EtcdVersion) error {
-	backupDir := fmt.Sprintf("%s/%s", m.dataDirectory, "migration-backup")
-	klog.Info("Backup etcd before starting migration")
-	err := os.Mkdir(backupDir, 0666)
-	if err != nil {
-		return fmt.Errorf("failed to create backup directory before starting migration: %v", err)
-	}
-	m.client.Backup(current, backupDir)
-	klog.Infof("Backup done in %s", backupDir)
-	return nil
-}
-
 func (m *Migrator) rollbackEtcd3MinorVersion(current *EtcdVersionPair, target *EtcdVersionPair) (*EtcdVersionPair, error) {
 	if target.version.Minor != current.version.Minor-1 {
 		return nil, fmt.Errorf("rollback from %s to %s not supported, only rollbacks to the previous minor version are supported", current.version, target.version)
@@ -191,56 +177,6 @@ func (m *Migrator) rollbackEtcd3MinorVersion(current *EtcdVersionPair, target *E
 	return target, nil
 }
 
-func (m *Migrator) rollbackToEtcd2(current *EtcdVersionPair, target *EtcdVersionPair) (*EtcdVersionPair, error) {
-	if !(current.version.Major == 3 && current.version.Minor == 0 && target.version.Major == 2 && target.version.Minor == 2) {
-		return nil, fmt.Errorf("etcd3 -> etcd2 downgrade is supported only between 3.0.x and 2.2.x, got current %s target %s", current, target)
-	}
-	klog.Info("Backup and remove all existing v2 data")
-	err := m.dataDirectory.Backup()
-	if err != nil {
-		return nil, err
-	}
-	err = RollbackV3ToV2(m.dataDirectory.path, time.Hour)
-	if err != nil {
-		return nil, fmt.Errorf("rollback to etcd 2.x failed: %v", err)
-	}
-	return target, nil
-
-}
-
-func (m *Migrator) etcd2ToEtcd3Upgrade(current *EtcdVersionPair, target *EtcdVersionPair) (*EtcdVersionPair, error) {
-	if current.storageVersion != storageEtcd2 || target.version.Major != 3 || target.storageVersion != storageEtcd3 {
-		return nil, fmt.Errorf("etcd2 to etcd3 upgrade is supported only for x.x.x/etcd2 to 3.0.x/etcd3, got current %s target %s", current, target)
-	}
-	runner := m.newServer()
-
-	klog.Info("Performing etcd2 -> etcd3 migration")
-	err := m.client.Migrate(target.version)
-	if err != nil {
-		return nil, err
-	}
-	klog.Info("Attaching leases to TTL entries")
-
-	// Now attach lease to all keys.
-	// To do it, we temporarily start etcd on a random port (so that
-	// apiserver actually cannot access it).
-	err = runner.Start(target.version)
-	if err != nil {
-		return nil, err
-	}
-	defer func() {
-		err = runner.Stop()
-	}()
-
-	// Create a lease and attach all keys to it.
-	err = m.client.AttachLease(1 * time.Hour)
-	if err != nil {
-		return nil, err
-	}
-
-	return target, err
-}
-
 func (m *Migrator) minorVersionUpgrade(current *EtcdVersionPair, target *EtcdVersionPair) (*EtcdVersionPair, error) {
 	runner := m.newServer()