private ReplicaLoc[] selectRandomReplicas() {
		ReplicaLoc[] result = new ReplicaLoc[NUM_REPLICA_PER_FILE];
		boolean[] visited = new boolean[replicaServerAddresses.length];
		for (int i = 0; i < result.length; i++) {
			int randomReplicaServer = rand(replicaServerAddresses.length);
			System.out.println(visited.length + " " + randomReplicaServer);
			while (visited[randomReplicaServer])
				randomReplicaServer = rand(replicaServerAddresses.length);
			visited[randomReplicaServer] = true;
			result[i] = replicaServerAddresses[randomReplicaServer];
		}
		return result;
	}