diff --git a/docker/l2tp/alpine/l2tp.sh b/docker/l2tp/alpine/l2tp.sh
index 103559b..4007e23 100644
--- a/docker/l2tp/alpine/l2tp.sh
+++ b/docker/l2tp/alpine/l2tp.sh
@@ -185,14 +185,18 @@ cat > /etc/ipsec.secrets <<EOF
 %any  %any  : PSK "${VPN_IPSEC_PSK}"
 EOF
 
-cat > /etc/ppp/chap-secrets <<EOF
+if ! grep -qw "${VPN_USER}" /etc/ppp/chap-secrets; then
+    cat > /etc/ppp/chap-secrets <<EOF
 ${VPN_USER} l2tpd ${VPN_PASSWORD} *
 EOF
+fi
 
 VPN_PASSWORD_ENC=$(openssl passwd -1 "${VPN_PASSWORD}")
-cat > /etc/ipsec.d/passwd <<EOF
+if ! grep -qw "${VPN_USER}" /etc/ipsec.d/passwd; then
+    cat > /etc/ipsec.d/passwd <<EOF
 ${VPN_USER}:${VPN_PASSWORD_ENC}:xauth-psk
 EOF
+fi
 
 chmod 600 /etc/ipsec.secrets /etc/ppp/chap-secrets /etc/ipsec.d/passwd
 
diff --git a/docker/l2tp/l2tp.sh b/docker/l2tp/l2tp.sh
index 103559b..4007e23 100644
--- a/docker/l2tp/l2tp.sh
+++ b/docker/l2tp/l2tp.sh
@@ -185,14 +185,18 @@ cat > /etc/ipsec.secrets <<EOF
 %any  %any  : PSK "${VPN_IPSEC_PSK}"
 EOF
 
-cat > /etc/ppp/chap-secrets <<EOF
+if ! grep -qw "${VPN_USER}" /etc/ppp/chap-secrets; then
+    cat > /etc/ppp/chap-secrets <<EOF
 ${VPN_USER} l2tpd ${VPN_PASSWORD} *
 EOF
+fi
 
 VPN_PASSWORD_ENC=$(openssl passwd -1 "${VPN_PASSWORD}")
-cat > /etc/ipsec.d/passwd <<EOF
+if ! grep -qw "${VPN_USER}" /etc/ipsec.d/passwd; then
+    cat > /etc/ipsec.d/passwd <<EOF
 ${VPN_USER}:${VPN_PASSWORD_ENC}:xauth-psk
 EOF
+fi
 
 chmod 600 /etc/ipsec.secrets /etc/ppp/chap-secrets /etc/ipsec.d/passwd