title: Hive Transactions + Remote Metastore Error
body: <p>I'm running Hive 2.1.1 on EMR 5.5.0 with a remote mysql metastore DB. I need to enable transactions on hive, but when I follow the configuration <a href="https://cwiki.apache.org/confluence/display/Hive/Hive+Transactions#HiveTransactions-Configuration" rel="nofollow noreferrer">here</a> and run any query, I get the following error </p>
  
  <blockquote>
    <p>FAILED: Error in acquiring locks: Error communicating with the metastore</p>
  </blockquote>
  
  <p>Settings on the metastore:</p>
  
  <pre><code>hive.compactor.worker.threads = 0
  hive.compactor.initiator.on = true
  </code></pre>
  
  <p>Settings in the hive client:</p>
  
  <pre><code>SET hive.support.concurrency=true;
  SET hive.enforce.bucketing=true;
  SET hive.exec.dynamic.partition.mode=nonstrict;
  SET hive.txn.manager=org.apache.hadoop.hive.ql.lockmgr.DbTxnManager;
  </code></pre>
  
  <p>This only happens when I set <code>hive.txn.manager</code>, so my hive metastore is definitely online.</p>
  
  <p>I've tried some of the old suggestions of turning hive test features on which didn't work, but I don't think this is a test feature anymore. I can't turn off concurrency as a similar post in SO suggests because I need concurrency. It seems like the problem is that either DbTxnManager isn't getting the remote metastore connection info properly from hive config or the mysqldb is missing some tables required by DbTxnManager. I have <code>datanucleus.autoCreateTables=true</code>.</p>