Merge pull request #58302 from deads2k/controller-05-id

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

uniquify resource lock identities

Resource lock identities on the same host were not unique.  This keeps the hostname (that's valuable), but also adds a UUID so that you can start a process twice on the same host and not end up with two processes trying to lead.

@kubernetes/sig-api-machinery-bugs @liggitt @smarterclayton

cmd/cloud-controller-manager/app/BUILD

@@ -23,6 +23,7 @@ go_library(
         "//vendor/github.com/prometheus/client_golang/prometheus:go_default_library",
         "//vendor/github.com/spf13/cobra:go_default_library",
         "//vendor/k8s.io/api/core/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/uuid:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/wait:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/server/healthz:go_default_library",
         "//vendor/k8s.io/client-go/informers:go_default_library",

cmd/cloud-controller-manager/app/controllermanager.go

@@ -33,6 +33,7 @@ import (
 	"github.com/spf13/cobra"
 
 	"k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/util/uuid"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/apiserver/pkg/server/healthz"
 	"k8s.io/client-go/informers"
@@ -169,6 +170,8 @@ func Run(s *options.CloudControllerManagerServer) error {
 	if err != nil {
 		return err
 	}
+	// add a uniquifier so that two processes on the same host don't accidentally both become active
+	id = id + "_" + string(uuid.NewUUID())
 
 	// Lock required for leader election
 	rl, err := resourcelock.New(s.LeaderElection.ResourceLock,

cmd/kube-controller-manager/app/BUILD

@@ -115,6 +115,7 @@ go_library(
         "//vendor/k8s.io/apimachinery/pkg/runtime/schema:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/runtime:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/sets:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/uuid:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/wait:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/server/healthz:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/util/feature:go_default_library",

cmd/kube-controller-manager/app/controllermanager.go

@@ -63,6 +63,7 @@ import (
 	"github.com/golang/glog"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/spf13/cobra"
+	"k8s.io/apimachinery/pkg/util/uuid"
 	"k8s.io/kubernetes/pkg/version/verflag"
 )
 
@@ -181,6 +182,8 @@ func Run(s *options.CMServer) error {
 	if err != nil {
 		return err
 	}
+	// add a uniquifier so that two processes on the same host don't accidentally both become active
+	id = id + "_" + string(uuid.NewUUID())
 
 	rl, err := resourcelock.New(s.LeaderElection.ResourceLock,
 		"kube-system",

cmd/kube-scheduler/app/BUILD

@@ -35,6 +35,7 @@ go_library(
         "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/runtime/serializer:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/runtime:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/uuid:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/wait:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/server/healthz:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/util/feature:go_default_library",

cmd/kube-scheduler/app/server.go

@@ -35,6 +35,7 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/serializer"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/apimachinery/pkg/util/uuid"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/apiserver/pkg/server/healthz"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
@@ -61,12 +62,11 @@ import (
 	"k8s.io/kubernetes/pkg/scheduler/algorithmprovider"
 	schedulerapi "k8s.io/kubernetes/pkg/scheduler/api"
 	latestschedulerapi "k8s.io/kubernetes/pkg/scheduler/api/latest"
+	"k8s.io/kubernetes/pkg/scheduler/factory"
 	"k8s.io/kubernetes/pkg/util/configz"
 	"k8s.io/kubernetes/pkg/version"
 	"k8s.io/kubernetes/pkg/version/verflag"
 
-	"k8s.io/kubernetes/pkg/scheduler/factory"
-
 	"github.com/golang/glog"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/spf13/cobra"
@@ -440,13 +440,15 @@ func makeLeaderElectionConfig(config componentconfig.KubeSchedulerLeaderElection
 	if err != nil {
 		return nil, fmt.Errorf("unable to get hostname: %v", err)
 	}
+	// add a uniquifier so that two processes on the same host don't accidentally both become active
+	id := hostname + "_" + string(uuid.NewUUID())
 
 	rl, err := resourcelock.New(config.ResourceLock,
 		config.LockObjectNamespace,
 		config.LockObjectName,
 		client.CoreV1(),
 		resourcelock.ResourceLockConfig{
-			Identity:      hostname,
+			Identity:      id,
 			EventRecorder: recorder,
 		})
 	if err != nil {