diff --git a/snap-overlay/bin/setup-br-ex b/snap-overlay/bin/setup-br-ex
index 0bb507c..710816c 100755
--- a/snap-overlay/bin/setup-br-ex
+++ b/snap-overlay/bin/setup-br-ex
@@ -18,6 +18,7 @@ ovs-vsctl --retry --may-exist add-br br-ex
 ip address add $extcidr dev br-ex || :
 ip link set br-ex up || :
 
-sudo iptables -w -t nat -A POSTROUTING -s $extcidr ! -d $extcidr -j MASQUERADE
+sudo iptables -w -t nat -A POSTROUTING -s $extcidr ! \
+     -d $extcidr -j MASQUERADE || :
 
 exit 0