Change NAT address block

[nodemanager-topo.git] / setup-nat

diff --git a/setup-nat b/setup-nat
index c835670..7eb87c6 100644 (file)
--- a/setup-nat
+++ b/setup-nat
@@ -9,22 +9,19 @@ KEY=$3
 
 modprobe etun
 
-###
-### Avoid IP address collisions between NAT and virtual links.
-### Virtual links have addresses 10.A.B.[23], where A < B always.
-### So make sure that A > B for NAT.
-###
-if [ $KEY > $NODEID ]; then
-    BASE="10.$KEY.$NODEID"
-else
-    BASE="10.$NODEID.$KEY"
-fi
+#
+# OpenVPN uses addresses in 10.<nodeid>/16 block.  Avoid collisions with
+# this block.  NAT interface is not advertised and so does not require
+# unique address throughout the topology.  But the address of each slice's
+# NAT interface must be unique on a single node.
+#
+BASE="10.0.$KEY"
 
 ### Setup etun
 ETUN0=nat$KEY
 ETUN1=natx$KEY
 echo $ETUN0,$ETUN1 > /sys/module/etun/parameters/newif
-ifconfig $ETUN1 $BASE.1 up
+ifconfig $ETUN1 $BASE.1/24 up
 
 /sbin/iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
 /sbin/iptables -A FORWARD -i eth0 -o $ETUN1 -m state --state RELATED,ESTABLISHED -j ACCEPT