title: postgres-9.4 claims data directory is missing, when it isn't
body: <p>I'm having trouble starting postgresql-9.4 on Centos 6.</p>
  
  <p>I can't run <code>initdb</code> because the data directory already exists.</p>
  
  <p>But I can't start the service because the data directory is missing!</p>
  
  <pre><code>[centos@dave-gbp ~]$ sudo service postgresql-9.4 start
  
  /var/lib/pgsql/9.4/data is missing. Use "service postgresql-9.4 initdb" to initialize the cluster first.
                                                         [FAILED]
  [centos@dave-gbp ~]$ sudo service postgresql-9.4 initdb
  Initializing database: mkdir: cannot create directory `/var/lib/pgsql/9.4/data/pg_log': File exists
                                                         [FAILED]
  </code></pre>
  
  <p>Any idea how I can get past this problem?</p>