diff --git a/script/_dhcpv6_pd_ref b/script/_dhcpv6_pd_ref
index 4d4e13fea06..06ccda8880c 100644
--- a/script/_dhcpv6_pd_ref
+++ b/script/_dhcpv6_pd_ref
@@ -2,18 +2,14 @@
 
 customise_dhcpcd_conf()
 {
+    # This has to be run after script/_border_routing, and this will 
+    # invalidate all changes to dhcpcd.conf made by script/_border_routing.
     sudo tee /etc/dhcpcd.conf >/dev/null <<EOF
 noipv6rs 
-# disable routing solicitation
+# disable router solicitation
 interface eth0
-  ipv6rs
   iaid 1
   ia_pd 2/::/64 -
-
-interface wlan0
-  ipv6rs
-  iaid 2
-  ia_pd 3/::/64 -
 EOF
 }
 
@@ -40,5 +36,4 @@ dhcpv6_pd_ref_install()
     # Add dhcpcd.hooks
     sudo install -m 755 "$(dirname "$0")"/reference-device/dhcpcd.enter-hook /etc/dhcpcd.enter-hook
     sudo install -m 755 "$(dirname "$0")"/reference-device/dhcpcd.exit-hook /etc/dhcpcd.exit-hook
-
 }
diff --git a/script/bootstrap b/script/bootstrap
index d6f8a6ad080..7c5ce223e96 100755
--- a/script/bootstrap
+++ b/script/bootstrap
@@ -106,8 +106,8 @@ install_packages_apt()
         fi
     }
 
-    # dhcpv6 pd
-    with DHCPV6_PD_REF && if command -v apt-get &>/dev/null; then
+    # dhcpv6-pd
+    without DHCPV6_PD_REF || {
         sudo apt-get install --no-install-recommends -y dhcpcd
         sudo mkdir -p /etc/systemd/system/dhcpcd.service.d
         # allow edit system config file eg. /etc/radvd.conf
@@ -118,7 +118,7 @@ EOF
         # reload dhcpcd daemon to activate the custom.conf
         sudo systemctl daemon-reload
         sudo apt-get install --no-install-recommends -y radvd
-    fi
+    }
 
     # network-manager
     without NETWORK_MANAGER || sudo apt-get install --no-install-recommends -y dnsmasq network-manager
diff --git a/script/reference-device/dhcpcd.enter-hook b/script/reference-device/dhcpcd.enter-hook
index 99566b33b36..bd02ccc65e2 100644
--- a/script/reference-device/dhcpcd.enter-hook
+++ b/script/reference-device/dhcpcd.enter-hook
@@ -1,7 +1,6 @@
 #!/bin/bash
 
-WAN_INTERFACE="eth0"
-WLAN_INTERFACE="wlan0"
+UPSTREAM_INTERFACE="eth0"
 WPAN_INTERFACE="wpan0"
 
 RADVD_CONF="/etc/radvd.conf"
@@ -29,7 +28,8 @@ EOF
 }
 
 
-if [ "${interface}" = "eth0" ] || [ “${interface}” = “wlan0” ]; then
+# TODO: set the upstream interface according to the environment variables of `script/setup`.
+if [ "${interface}" = ${UPSTREAM_INTERFACE} ]; then
 
     for var in $(env); do
         # Split the variable into name and value
diff --git a/script/reference-device/dhcpcd.exit-hook b/script/reference-device/dhcpcd.exit-hook
index 8aba12527d5..ce79b9385cd 100644
--- a/script/reference-device/dhcpcd.exit-hook
+++ b/script/reference-device/dhcpcd.exit-hook
@@ -2,8 +2,7 @@
 #dhcpcd.exit-hook
 
 
-WAN_INTERFACE="eth0"
-WLAN_INTERFACE="wlan0"
+UPSTREAM_INTERFACE="eth0"
 WPAN_INTERFACE="wpan0"
 
 RADVD_CONF="/etc/radvd.conf"
@@ -29,7 +28,9 @@ interface ${WPAN_INTERFACE}
 EOF
 }
 
-if [ “${interface}” = “eth0” ] || [ “${interface}” = “wlan0” ]; then
+
+# TODO: set the upstream interface according to the environment variables of `script/setup`.
+if [ “${interface}” = ${UPSTREAM_INTERFACE} ]; then
 
     for var in $(env); do
         # Split the variable into name and value