--- /dev/null
+#!/bin/sh
+
+# set IP MASQUERADE with post-up command in INTERFACES(5)
+
+
+set -x
+
+## INTERFACES(5)
+# IFACE physical name of the interface being processed
+# METHOD method of the interface (e.g., static)\r
+# MODE start if run from ifup, stop if run from ifdown\r
+# PHASE as per MODE, but with finer granularity, distinguishing the pre-\r
+# up, post-up, pre-down and post-down phases.\r
+
+# optional argument to set default gateway devices connected to WAN manually
+# (try each of them in order)
+
+if [ "${PHASE}" = "post-down" ]; then
+ # remove MASQUERADE rule and exit
+ /sbin/iptables -t nat -D POSTROUTING -o ${IFACE} -j MASQUERADE
+ exit
+fi
+
+
+# set MASQUERADE rule
+/sbin/iptables -t nat -A POSTROUTING -o ${IFACE} -j MASQUERADE