title: Data nodes cannot connect to MySQL Cluster
body: <p>I have a problem with my MySQL Cluster running on AWS EC2 instances (3 data nodes and 1 management node, on t2.micro running Ubuntu latest version). I followed this tutorial (with updated version of MySQL Cluster 7.5.5) : <a href="https://stansantiago.wordpress.com/2012/01/04/installing-mysql-cluster-on-ec2/" rel="nofollow noreferrer">https://stansantiago.wordpress.com/2012/01/04/installing-mysql-cluster-on-ec2/</a></p>
  
  <p>In <code>my.cnf</code> file, I have the following code : </p>
  
  <pre><code>[mysqld]
  ndbcluster
  datadir=/opt/mysqlcluster/deploy/mysqld_data
  basedir=/opt/mysqlcluster/home/mysqlc
  port=3306
  </code></pre>
  
  <p>In <code>config.ini</code> file, I have this code :</p>
  
  <pre><code>[ndb_mgmd]
  hostname=&lt;private DNS of master&gt;
  datadir=/opt/mysqlcluster/deploy/ndb_data
  nodeid=1
  
  [ndbd default]
  noofreplicas=3
  datadir=/opt/mysqlcluster/deploy/ndb_data
  
  [ndbd]
  hostname=&lt;private DNS of slave 1&gt;
  nodeid=3
  
  [ndbd]
  hostname=&lt;private DNS of slave 2&gt;
  nodeid=4
  
  [ndbd]
  hostname=&lt;private DNS of slave 3&gt;
  nodeid=5
  
  [mysqld]
  nodeid=50
  </code></pre>
  
  <p>Then I start the management node like this : </p>
  
  <pre><code>ndb_mgmd -f /opt/mysqlcluster/deploy/conf/config.ini --initial --configdir=/opt/mysqlcluster/deploy/conf
  </code></pre>
  
  <p>Everything seems fine, I have no error displayed.</p>
  
  <p>However, when I try to connect a slave to the cluster, with this command : </p>
  
  <pre><code>ndbd -c &lt;private DNS of master&gt;:1186
  </code></pre>
  
  <p>it fails with this error code :</p>
  
  <pre><code>Unable to connect with connect string: nodeid=0,&lt;private DNS of master&gt;:1186
  </code></pre>
  
  <p>I tried the command <code>ndb_mgm -e show</code> to see what was going on : </p>
  
  <pre><code>Connected to Management Server at: localhost:1186
  Cluster Configuration
  ---------------------
  [ndbd(NDB)] 3 node(s)
  id=3 (not connected, accepting connect from &lt;private DNS of slave 1&gt;)
  id=4 (not connected, accepting connect from &lt;private DNS of slave 2&gt;)
  id=5 (not connected, accepting connect from &lt;private DNS of slave 2&gt;)
  
  [ndb_mgmd(MGM)] 1 node(s)
  id=1    @&lt;private IP address of master&gt;  (mysql-5.7.17 ndb-7.5.5)
  
  [mysqld(API)]   1 node(s)
  id=50 (not connected, accepting connect from any host)
  </code></pre>
  
  <p>It seems that the management node started on localhost, is this why it fails ?
  I don't understand why I can't connect the data nodes to the cluster because the configuration files look good.</p>
  
  <p>If somebody has any suggestion, it would be much appreciated. Thank you !</p>