diff --git a/config_generator/wg-external.conf b/config_generator/wg-external.conf
index 84b361d..73291ff 100644
--- a/config_generator/wg-external.conf
+++ b/config_generator/wg-external.conf
@@ -1,8 +1,8 @@
 [Interface]
 Address = 10.20.30.2/32
 PrivateKey = ---PRIVATE_KEY_EXTERNAL---
-PostUp = iptables -t nat -A POSTROUTING -o `ip link show | awk -F ': ' '/state UP/ {print $2}'` -j MASQUERADE
-PostDown = iptables -t nat -D POSTROUTING -o `ip link show | awk -F ': ' '/state UP/ {print $2}'` -j MASQUERADE
+PostUp = iptables -t nat -A POSTROUTING -o `ip route | awk '/default/ {print $5; exit}'` -j MASQUERADE
+PostDown = iptables -t nat -D POSTROUTING -o `ip route | awk '/default/ {print $5; exit}'` -j MASQUERADE
 
 #internal node
 [Peer]
diff --git a/config_generator/wg-internal.conf b/config_generator/wg-internal.conf
index 4d8f32a..1fabeef 100644
--- a/config_generator/wg-internal.conf
+++ b/config_generator/wg-internal.conf
@@ -2,9 +2,9 @@
 Address = 10.20.30.1/32
 ListenPort = 17968
 PrivateKey = ---PRIVATE_KEY_INTERNAL---
-PostUp = iptables -t nat -A POSTROUTING -o `ip link show | awk -F ': ' '/state UP/ {print $2}'` -j MASQUERADE
+PostUp = iptables -t nat -A POSTROUTING -o `ip route | awk '/default/ {print $5; exit}'` -j MASQUERADE
 PostUp = ip rule add from `ip route | awk '/default/ {print $3; exit}'` table main
-PostDown = iptables -t nat -D POSTROUTING -o `ip link show | awk -F ': ' '/state UP/ {print $2}'` -j MASQUERADE
+PostDown = iptables -t nat -D POSTROUTING -o `ip route | awk '/default/ {print $5; exit}'` -j MASQUERADE
 PostDown = ip rule del from `ip route | awk '/default/ {print $3; exit}'` table main
 
 #external node
diff --git a/sample_wg_cfg/wg-external.conf b/sample_wg_cfg/wg-external.conf
index 4044a23..965fb9c 100644
--- a/sample_wg_cfg/wg-external.conf
+++ b/sample_wg_cfg/wg-external.conf
@@ -1,8 +1,8 @@
 [Interface]
 Address=10.20.30.2/32
 PrivateKey=6CCRP42JiTObyf64Vo0BcqsX6vptsqOU+MKUslUun28=
-PostUp = iptables -t nat -A POSTROUTING -o `ip link show | awk -F ': ' '/state UP/ {print $2}'` -j MASQUERADE
-PostDown = iptables -t nat -D POSTROUTING -o `ip link show | awk -F ': ' '/state UP/ {print $2}'` -j MASQUERADE
+PostUp = iptables -t nat -A POSTROUTING -o `ip route | awk '/default/ {print $5; exit}'` -j MASQUERADE
+PostDown = iptables -t nat -D POSTROUTING -o `ip route | awk '/default/ {print $5; exit}'` -j MASQUERADE
 
 #internal node
 [Peer]
diff --git a/sample_wg_cfg/wg-internal.conf b/sample_wg_cfg/wg-internal.conf
index c025637..b8e43c1 100644
--- a/sample_wg_cfg/wg-internal.conf
+++ b/sample_wg_cfg/wg-internal.conf
@@ -2,9 +2,9 @@
 Address = 10.20.30.1/32
 ListenPort = 17968
 PrivateKey = kOd3FVBggwpjD3AlZKXUxNTzJT0+f3MJdUdR8n6ZBn8=
-PostUp = iptables -t nat -A POSTROUTING -o `ip link show | awk -F ': ' '/state UP/ {print $2}'` -j MASQUERADE
+PostUp = iptables -t nat -A POSTROUTING -o `ip route | awk '/default/ {print $5; exit}'` -j MASQUERADE
 PostUp = ip rule add from `ip route | awk '/default/ {print $3; exit}'` table main
-PostDown = iptables -t nat -D POSTROUTING -o `ip link show | awk -F ': ' '/state UP/ {print $2}'` -j MASQUERADE
+PostDown = iptables -t nat -D POSTROUTING -o `ip route | awk '/default/ {print $5; exit}'` -j MASQUERADE
 PostDown = ip rule del from `ip route | awk '/default/ {print $3; exit}'` table main
 
 #external node