MongoDB connection refused to local node when connecting to replica set

Question

I have a replica set consisting of four nodes (ux002, ux009, ux019, ux020). I have a program that I'd like to run in parallel on each of the same four nodes which connects to this replica set using the Mongo Java driver.

Examining the status of the replica set shows that all four nodes are operating fine, however the program throws the following warning message on all four nodes:

Nov 12, 2014 2:34:40 PM com.mongodb.ConnectionStatus$UpdatableNode update WARNING: Server seen down: ux009/127.0.1.1:27017 - java.io.IOException - message: couldn't connect to [ux009/127.0.1.1:27017] bc:java.net.ConnectException: Connection refused

However, on each node, the server which is seen down is the one the program is running on. I.e. I run the program on ux009, and it tells me ux009 is down. I run it on ux002, it tells me ux002 is down.

I made a stupidly simple program to test whether there was something wrong with my original code, but the same warning persists:

public static void main(String[] args) throws Exception {
  List<ServerAddress> addrs = new ArrayList<>();

  if (args.length == 0) {
    addrs.add(new ServerAddress("localhost", 27017));
  } else {
    for (String a : args) {
      String[] host = a.split(":");
      addrs.add(new ServerAddress(host[0], Integer.valueOf(host[1])));
    }
  }

  mongo = new Mongo(addrs);
  Thread.sleep(5000); // Sleep to give it time to print messages
  mongo.close();
}

And I run it as follows:

java -jar mongo-test.jar ux002:27017 ux009:27017 ux019:27017 ux020:27017

Could it be that mongod isn't configured correctly? Or perhaps I am misusing the Java API?

The Mongo Java driver is version 2.9.3, and mongod is version 2.6.5.

Many thanks in advance! -Jim

Answer 1

Posting the answer here for completeness. The issue was that the bind_ip parameter in the mongod configuration file had been set to the IP address of only one of the nodes. Thanks to helmy for spotting that.

Answer 2

The IP is a little strange for the local host:

ux009/127.0.1.1:27017

I would have expected that to be:

ux009/127.0.0.1:27017

Most likely someone fat fingered the ip address in the /etc/hosts on each machine.