Flip result code when checking for new peer

This avoids mistaking an error condition for the result we should act on

prog/kube-peers/main.go

@@ -182,7 +182,7 @@ func main() {
 		logLevel    string
 	)
 	flag.BoolVar(&justReclaim, "reclaim", false, "reclaim IP space from dead peers")
-	flag.BoolVar(&justCheck, "check-peer-exists", false, "return success if peer name is stored in annotation")
+	flag.BoolVar(&justCheck, "check-peer-new", false, "return success if peer name is not stored in annotation")
 	flag.StringVar(&peerName, "peer-name", "unknown", "name of this Weave Net peer")
 	flag.StringVar(&nodeName, "node-name", "unknown", "name of this Kubernetes node")
 	flag.StringVar(&logLevel, "log-level", "info", "logging level (debug, info, warning, error)")
@@ -204,9 +204,9 @@ func main() {
 			common.Log.Fatalf("[kube-peers] Could not check peer list: %v", err)
 		}
 		if exists {
-			os.Exit(0)
-		} else {
 			os.Exit(9)
+		} else {
+			os.Exit(0)
 		}
 	}
 	peers, err := getKubePeers(c)

prog/weave-kube/launch.sh

@@ -98,7 +98,7 @@ fi
 # If this peer name is not stored in the list, either we are a
 # brand-new peer or we were removed by another peer while temporarily
 # absent. In order to avoid a CRDT clash for the latter case, clean up
-if ! /home/weave/kube-peers -check-peer-exists -peer-name="$PEERNAME" -log-level=debug ; then
+if /home/weave/kube-peers -check-peer-new -peer-name="$PEERNAME" -log-level=debug ; then
     if [ -f ${DB_PREFIX}data.db ]; then
         echo "Peer not in list; removing persisted data" >&2
         rm -f ${DB_PREFIX}data.db