title: Greenplum Database :psql: could not connect to server: No such file or directory
body: <p>I am bashing my head against the wall. its been 4 days.but psql is not connecting.</p>
  
  <p>We have a small array of Greenplum database.In that, We have the master node. when i am trying to use psql utility</p>
  
  <p>Getting this error :</p>
  
  <pre><code>[gpadmin@master gpseg-1]$ psql
  psql: could not connect to server: No such file or directory
  Is the server running locally and accepting
  connections on Unix domain socket "/tmp/.s.PGSQL.5432"?
  </code></pre>
  
  <p><strong>We tried</strong></p>
  
  <p>on searching for postmaster.pid  files. </p>
  
  <p>We have removed it.But still, error remains. </p>