diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index e43068f..5baf181 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -96,9 +96,6 @@ jobs:
           context: .
           file: ./cmd/nclet/Dockerfile
           push: true
-          build-args: |
-            DEFAULT_SSH_USERNAME=${{ secrets.NCLET_DEFAULT_SSH_USERNAME }}
-            DEFAULT_SSH_PASSWORD=${{ secrets.NCLET_DEFAULT_SSH_PASSWORD }}
           tags: |
             asia-northeast1-docker.pkg.dev/networkcontest/janog55/netcon-pms-nclet:latest
             asia-northeast1-docker.pkg.dev/networkcontest/janog55/netcon-pms-nclet:master
diff --git a/cmd/access-helper/labels.go b/cmd/access-helper/labels.go
index e0577b5..fe9fc76 100644
--- a/cmd/access-helper/labels.go
+++ b/cmd/access-helper/labels.go
@@ -2,6 +2,16 @@ package main
 
 // These are the label keys that we can customize how to access Node in ContainerLab.
 const (
+	// defaultUsername is a default username for SSH access.
+	// You can override this value when building access-helper with -ldflags.
+	// ref: https://uokada.hatenablog.jp/entry/2015/05/20/001208
+	defaultSSHUsername string = "clab"
+
+	// defaultPassword is a default password for SSH access.
+	// You can override this value when building access-helper with -ldflags.
+	// ref: https://uokada.hatenablog.jp/entry/2015/05/20/001208
+	defaultSSHPassword string = "clab@123"
+
 	// AccessMethodKey is the label key to specify the access method.
 	// The possible values are either "ssh" or "exec".
 	// With "ssh", access-helper will try to connect to the Node via SSH.
@@ -38,15 +48,3 @@ const (
 	execCommandKey     = "netcon.janog.gr.jp/execCommand"
 	defaultExecCommand = "sh"
 )
-
-var (
-	// defaultUsername is a default username for SSH access.
-	// You can override this value when building access-helper with -ldflags.
-	// ref: https://uokada.hatenablog.jp/entry/2015/05/20/001208
-	defaultSSHUsername string
-
-	// defaultPassword is a default password for SSH access.
-	// You can override this value when building access-helper with -ldflags.
-	// ref: https://uokada.hatenablog.jp/entry/2015/05/20/001208
-	defaultSSHPassword string
-)
diff --git a/cmd/nclet/Dockerfile b/cmd/nclet/Dockerfile
index bf26977..2b6fa2b 100644
--- a/cmd/nclet/Dockerfile
+++ b/cmd/nclet/Dockerfile
@@ -22,9 +22,6 @@ RUN --mount=type=cache,target=/root/.cache/go-build CGO_ENABLED=0 go build -o nc
 # Build the access-helper binary
 FROM golang:1.23 as access-helper_builder
 
-ARG DEFAULT_SSH_USERNAME
-ARG DEFAULT_SSH_PASSWORD
-
 WORKDIR /workspace
 COPY go.mod go.mod
 COPY go.sum go.sum
@@ -36,8 +33,7 @@ COPY pkg/ pkg/
 
 # Build
 RUN --mount=type=cache,target=/root/.cache/go-build CGO_ENABLED=0 \
-    go build -o access-helper -ldflags="-X main.defaultSSHUsername=${DEFAULT_SSH_USERNAME} -X main.defaultSSHPassword=${DEFAULT_SSH_PASSWORD}" ./cmd/access-helper
-
+    go build -o access-helper ./cmd/access-helper
 
 # Build the containerlab binary
 FROM golang:1.23 as containerlab_builder