Leave container allocations for a time after death

so they will be reclaimed if the container is restarted.
Still cancel pending operations immediately a container dies

test/640_proxy_restart_reattaches_test.sh

@@ -2,8 +2,6 @@
 
 . ./config.sh
 
-C1=10.2.0.78
-C2=10.2.0.34
 NAME=seetwo.weave.local
 
 check_attached() {
@@ -26,8 +24,9 @@ wait_for_proxy() {
 start_suite "Proxy restart reattaches networking to containers"
 
 WEAVE_DOCKER_ARGS=--restart=always WEAVEPROXY_DOCKER_ARGS=--restart=always weave_on $HOST1 launch
-proxy_start_container          $HOST1 -e WEAVE_CIDR=$C2/24 -di --name=c2 --restart=always -h $NAME
-proxy_start_container_with_dns $HOST1 -e WEAVE_CIDR=$C1/24 -di --name=c1 --restart=always
+proxy_start_container          $HOST1 -di --name=c2 --restart=always -h $NAME
+proxy_start_container_with_dns $HOST1 -di --name=c1 --restart=always
+C2=$(container_ip $HOST1 c2)
 
 proxy docker_on $HOST1 restart -t=1 c2
 check_attached
@@ -42,11 +41,13 @@ run_on $HOST1 sudo kill -KILL $(docker_on $HOST1 inspect --format='{{.State.Pid}
 sleep 1
 check_attached
 
-# Disabled because Docker 1.8 often fails to restart weave or weaveproxy
 # Restart docker itself, using different commands for systemd- and upstart-managed.
-#run_on $HOST1 sh -c "command -v systemctl >/dev/null && sudo systemctl restart docker || sudo service docker restart"
-#wait_for_proxy $HOST1
-#check_attached
+run_on $HOST1 sh -c "command -v systemctl >/dev/null && sudo systemctl restart docker || sudo service docker restart"
+wait_for_proxy $HOST1
+sleep 5 # allow for re-tries of attach
+# Re-fetch the IP since it is not retained on docker restart
+C2=$(container_ip $HOST1 c2) || (echo "container c2 has no IP address" 2>&1; exit 1)
+check_attached
 
 # Restarting proxy shouldn't kill unattachable containers
 proxy_start_container $HOST1 -di --name=c3 --restart=always # Use ipam, so it won't be attachable w/o weave