diff --git a/.circleci/config.yml b/.circleci/config.yml
index 841e50007..6e7def2d5 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -57,10 +57,15 @@ jobs:
           command: |
             ./bin/watch_boot0
           background: true
+      - run:
+          name: Watch neco-updater logs
+          command: |
+            ./bin/watch_service neco-updater
+          background: true
       - run:
           name: Watch neco-worker logs
           command: |
-            ./bin/watch_neco_worker
+            ./bin/watch_service neco-worker
           background: true
       - run:
           command: |
@@ -120,11 +125,17 @@ jobs:
             if [ ! -f .diff ]; then exit 0; fi
             ./bin/watch_boot0
           background: true
+      - run:
+          name: Watch neco-updater logs
+          command: |
+            if [ ! -f .diff ]; then exit 0; fi
+            ./bin/watch_service neco-updater
+          background: true
       - run:
           name: Watch neco-worker logs
           command: |
             if [ ! -f .diff ]; then exit 0; fi
-            ./bin/watch_neco_worker
+            ./bin/watch_service neco-worker
           background: true
       - run:
           command: |
diff --git a/bin/watch_neco_worker b/bin/watch_service
similarity index 52%
rename from bin/watch_neco_worker
rename to bin/watch_service
index 7b22b2037..c8e1c76b2 100755
--- a/bin/watch_neco_worker
+++ b/bin/watch_service
@@ -2,18 +2,21 @@
 
 . $(dirname $0)/env
 
-tail_neco_worker_once() {
+test $# -eq 1
+service="$1"
+
+tail_once() {
   host="$1"
   $GCLOUD 2>/dev/null compute ssh --zone=${ZONE} cybozu@${INSTANCE_NAME} -- \
     sudo nsenter -n -t '$(sudo pmctl pod show operation | jq .pid)' ssh -F ssh_config \
-     ${host} journalctl -f -u neco-worker.service
+     ${host} journalctl -f -u ${service}.service
 }
 
-tail_neco_worker() {
+tail_forever() {
   host="$1"
 
   while true; do
-    tail_neco_worker_once $host || continue
+    tail_once $host || continue
     sleep 3
   done
 }
@@ -23,9 +26,9 @@ while ! $GCLOUD 2>/dev/null compute scp --zone=${ZONE} ./dctest/dctest_key ./dct
     sleep 1
 done
 
-tail_neco_worker boot-0 | sed -e s/^/$(tput -Txterm setaf 1)/ &
-tail_neco_worker boot-1 | sed -e s/^/$(tput -Txterm setaf 2)/ &
-tail_neco_worker boot-2 | sed -e s/^/$(tput -Txterm setaf 3)/ &
-tail_neco_worker boot-3 | sed -e s/^/$(tput -Txterm setaf 4)/ &
+tail_forever boot-0 | sed -e s/^/$(tput -Txterm setaf 1)/ &
+tail_forever boot-1 | sed -e s/^/$(tput -Txterm setaf 2)/ &
+tail_forever boot-2 | sed -e s/^/$(tput -Txterm setaf 3)/ &
+tail_forever boot-3 | sed -e s/^/$(tput -Txterm setaf 4)/ &
 
 wait
diff --git a/docs/neco.md b/docs/neco.md
index 8558470cf..2aef69971 100644
--- a/docs/neco.md
+++ b/docs/neco.md
@@ -125,11 +125,13 @@ These configurations are stored in etcd database.
 
 ### `env`
 
-Specify the cluster environment.  The default is `staging`.
+Specify the cluster environment.
 Possible values are: `staging` and `prod`.
 
 `staging` environment will be updated with pre-releases of `neco` package.
 
+Update never happens until this config is set.
+
 ### `slack`
 
 Specify [Slack WebHook](https://api.slack.com/incoming-webhooks) URL.
diff --git a/docs/update.md b/docs/update.md
index 1d0919b99..16f4c105a 100644
--- a/docs/update.md
+++ b/docs/update.md
@@ -58,7 +58,7 @@ use the version number `2018.11.07-1` on a comparison of the tags.
 must select the environment by `neco config set env ENV` sub-command.
 If `production` is set, `neco-updater` downloads latest release excluding
 pre-release version.  Otherwise if `staging` is set, `neco-updater` downloads
-latest pre-release version.
+latest version from among releases and pre-releases.
 
 Implementation of update process
 --------------------------------
diff --git a/pkg/neco/cmd/config_set.go b/pkg/neco/cmd/config_set.go
index 9922235b0..8b5a47a02 100644
--- a/pkg/neco/cmd/config_set.go
+++ b/pkg/neco/cmd/config_set.go
@@ -22,7 +22,7 @@ var configSetCmd = &cobra.Command{
 	Long: `Store a configuration value to etcd.
 
 Possible keys are:
-    env                   - "staging" or "prod".  Default is "staging".
+    env                   - "staging" or "prod".
     slack                 - Slack WebHook URL.
     proxy                 - HTTP proxy server URL to access Internet.
     quay-username         - Username to authenticate to quay.io from QUAY_USER.  This does not take VALUE.
diff --git a/storage/config.go b/storage/config.go
index d413c7429..f48e26b8a 100644
--- a/storage/config.go
+++ b/storage/config.go
@@ -23,7 +23,7 @@ func (s Storage) PutEnvConfig(ctx context.Context, env string) error {
 func (s Storage) GetEnvConfig(ctx context.Context) (string, error) {
 	env, err := s.get(ctx, KeyEnv)
 	if err == ErrNotFound {
-		return neco.StagingEnv, nil
+		return neco.NoneEnv, nil
 	}
 	return env, err
 }
diff --git a/storage/config_test.go b/storage/config_test.go
index 30099b361..944420296 100644
--- a/storage/config_test.go
+++ b/storage/config_test.go
@@ -21,21 +21,21 @@ func testEnvConfig(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if env != neco.StagingEnv {
-		t.Error(`env != neco.StagingEnv`, env)
+	if env != neco.NoneEnv {
+		t.Error(`env != neco.NoneEnv`, env)
 	}
 
-	err = st.PutEnvConfig(ctx, "http://squid.example.com:3128")
+	err = st.PutEnvConfig(ctx, neco.StagingEnv)
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	proxy, err := st.GetEnvConfig(ctx)
+	env, err = st.GetEnvConfig(ctx)
 	if err != nil {
 		t.Fatal(err)
 	}
-	if proxy != "http://squid.example.com:3128" {
-		t.Error(`proxy != "http://squid.example.com:3128"`, proxy)
+	if env != neco.StagingEnv {
+		t.Error(`env != neco.StagingEnv"`, env)
 	}
 }
 
diff --git a/update.go b/update.go
index 7a78a7f63..52eee27e5 100644
--- a/update.go
+++ b/update.go
@@ -4,6 +4,7 @@ import "time"
 
 // Environments to use release or pre-release neco
 const (
+	NoneEnv    = "none"
 	TestEnv    = "test"
 	StagingEnv = "staging"
 	ProdEnv    = "prod"
diff --git a/updater/github.go b/updater/github.go
index a41f6bd68..ee5406e5b 100644
--- a/updater/github.go
+++ b/updater/github.go
@@ -20,7 +20,7 @@ type ReleaseClient struct {
 	http  *http.Client
 }
 
-// GetLatestReleaseTag returns latest tag in GitHub Releases of neco repository
+// GetLatestReleaseTag returns latest published release tag in GitHub Releases of neco repository
 func (c ReleaseClient) GetLatestReleaseTag(ctx context.Context) (string, error) {
 	client := neco.NewGitHubClient(c.http)
 	release, resp, err := client.Repositories.GetLatestRelease(ctx, c.owner, c.repo)
@@ -46,8 +46,8 @@ func (c ReleaseClient) GetLatestReleaseTag(ctx context.Context) (string, error)
 	return *release.TagName, nil
 }
 
-// GetLatestPreReleaseTag returns latest pre-released tag in GitHub Releases of neco repository
-func (c ReleaseClient) GetLatestPreReleaseTag(ctx context.Context) (string, error) {
+// GetLatestPublishedTag returns latest published release/pre-release tag in GitHub Releases of neco repository
+func (c ReleaseClient) GetLatestPublishedTag(ctx context.Context) (string, error) {
 	client := neco.NewGitHubClient(c.http)
 
 	opt := &github.ListOptions{
@@ -68,7 +68,7 @@ func (c ReleaseClient) GetLatestPreReleaseTag(ctx context.Context) (string, erro
 	}
 	versions := make([]*version.Version, 0, len(releases))
 	for _, r := range releases {
-		if r.TagName == nil || !r.GetPrerelease() {
+		if r.TagName == nil || r.GetDraft() {
 			continue
 		}
 		s := *r.TagName
diff --git a/updater/github_test.go b/updater/github_test.go
index 196fc3649..b956f8688 100644
--- a/updater/github_test.go
+++ b/updater/github_test.go
@@ -16,11 +16,11 @@ func testGetLatestReleaseTag(t *testing.T) {
 	t.Logf("version = %s", ver)
 }
 
-func testGetLatestPreReleaseTag(t *testing.T) {
+func testGetLatestPublishedTag(t *testing.T) {
 	t.Skip()
 
 	c := ReleaseClient{owner: "kubernetes", repo: "kubernetes"}
-	ver, err := c.GetLatestPreReleaseTag(context.Background())
+	ver, err := c.GetLatestPublishedTag(context.Background())
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -32,5 +32,5 @@ func testGetLatestPreReleaseTag(t *testing.T) {
 
 func TestGitHub(t *testing.T) {
 	t.Run("GetLatestReleaseTag", testGetLatestReleaseTag)
-	t.Run("GetLatestPreReleaseTag", testGetLatestPreReleaseTag)
+	t.Run("GetLatestPublishedTag", testGetLatestPublishedTag)
 }
diff --git a/updater/release_checker.go b/updater/release_checker.go
index b3de12e32..59b149ebf 100644
--- a/updater/release_checker.go
+++ b/updater/release_checker.go
@@ -42,12 +42,16 @@ func (c *ReleaseChecker) Run(ctx context.Context) error {
 	}
 
 	switch env {
+	case neco.NoneEnv:
+		c.check = func(ctx context.Context) (string, error) {
+			return "", ErrNoReleases
+		}
 	case neco.TestEnv:
 		c.check = func(ctx context.Context) (string, error) {
 			return "0.0.2", nil
 		}
 	case neco.StagingEnv:
-		c.check = github.GetLatestPreReleaseTag
+		c.check = github.GetLatestPublishedTag
 	case neco.ProdEnv:
 		c.check = github.GetLatestReleaseTag
 	default: