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diff --git a/vnfs/vLB/DNSManager/src/main/java/DNSMembershipManager.java b/vnfs/vLB/DNSManager/src/main/java/DNSMembershipManager.java
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+
+/*************************************************************************//**
+ *
+ * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ ****************************************************************************/
+
+package main.java;
+
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Set;
+
+public class DNSMembershipManager {
+	/*
+	 * Uses Failure Detector (FD) to keep track of the DNS servers currently active.
+	 * @param port: the port that the FD service listens for incoming UDP packets
+	 * @param timeout: how often the FD checks the status of client processes
+	 * @param threshold: number of missing ping messages before declaring a client dead
+	 * @param debug: debug mode on/off
+	 */
+	
+	static Set<String> active = new HashSet<String>();
+	
+	@SuppressWarnings("static-access")
+	public static void main(String[] args) throws IOException, InterruptedException {
+		if(args.length != 5) {
+			System.out.println("Missing input parameters");
+			System.out.println("Usage:");
+			System.out.print("\t- java FDServer [public IP address] [port] [timeout (sec)] [threshold] [debug]\n");
+			System.exit(0);
+		}
+		
+		// Input parameters: PORT, TIMEOUT, THRESHOLD
+		String IPADDR = args[0];
+		int PORT = Integer.parseInt(args[1]);
+		long TIMEOUT = Long.parseLong(args[2]) * 1000; // convert the FD timeout to milliseconds
+		int THRESHOLD = Integer.parseInt(args[3]);
+		int debug = Integer.parseInt(args[4]);
+		boolean DEBUG;
+		if(debug <= 0)
+			DEBUG = false;
+		else
+			DEBUG = true;
+		
+		// Start Failure Detector
+		FDServer fd = new FDServer(IPADDR, PORT, TIMEOUT, THRESHOLD, DEBUG);
+		
+		// Check the status of client processes periodically. We use the same timeout value as FD
+		Set<String> active = new HashSet<String>();
+		while(true) {
+			Set<String> alive_this_round = fd.getAliveProcesses();
+			Iterator<String> iter = alive_this_round.iterator();
+			String pid;
+			
+			// Check if there is some new DNS active
+			while(iter.hasNext()) {
+				pid = iter.next();
+				if(!active.contains(pid)) {
+					active.add(pid);
+					// Add the new vDNS to the set of vDNS servers
+					String script = new String("bash /opt/FDserver/add_dns.sh " + pid);
+		            Runtime.getRuntime().exec(script);
+					if(DEBUG) System.out.println("Adding process " + pid + " to the list of DNSs");
+				}
+			}
+			
+			// Remove possible dead DNSs
+			iter = active.iterator();
+			while(iter.hasNext()) {
+				pid = iter.next();
+				if(!alive_this_round.contains(pid)) {
+					iter.remove(); // remove element from the iterator to avoid ConcurrentModificationException
+					// Remove the new vDNS from the set of vDNS servers
+					String script = new String("bash /opt/FDserver/remove_dns.sh " + pid);
+		            Runtime.getRuntime().exec(script);
+					if(DEBUG) System.out.println("Removing process " + pid + " from the list of DNSs");
+				}
+			}
+			Thread.currentThread().sleep(TIMEOUT);
+		}
+	}
+}