title: Lost databases in Postgres after restart
body: <p>Firstly I am a novice Postgres SQL user. I have installed Postgres in EC2 instance which has two volumes, one root volume, and another data volume.</p>
  
  <p>I have 4 working databases and when I stop and start the instance, I am not able to connect to those databases.</p>
  
  <p>These are the processes running after rebooting the machine.</p>
  
  <pre><code>ps aux | grep post
  postgres  2569  0.0  1.3 230400 13484 ?        S    07:24   0:00 /usr/lib64/pgsql92/bin/postmaster -p 5432 -D /var/lib/pgsql9/data
  postgres  2571  0.0  0.3 190148  3748 ?        Ss   07:24   0:00 postgres: logger process                                         
  postgres  2573  0.0  0.3 230400  3944 ?        Ss   07:24   0:00 postgres: checkpointer process                                   
  postgres  2574  0.0  0.4 230400  5048 ?        Ss   07:24   0:00 postgres: writer process                                         
  postgres  2575  0.0  0.3 230400  3944 ?        Ss   07:24   0:00 postgres: wal writer process                                     
  postgres  2576  0.0  0.6 231220  6388 ?        Ss   07:24   0:00 postgres: autovacuum launcher process                            
  postgres  2577  0.0  0.4 190144  4616 ?        Ss   07:24   0:00 postgres: stats collector process                                
  root      2812  0.0  0.4 192244  4084 pts/0    S    07:25   0:00 su postgres
  postgres  2813  0.0  0.3 113444  3256 pts/0    S    07:25   0:00 bash
  postgres  2941  0.0  0.1 115276  1988 pts/0    R+   08:15   0:00 ps aux
  postgres  2942  0.0  0.1 110440  1812 pts/0    S+   08:15   0:00 grep pos
  </code></pre>
  
  <p>Could anyone please help me.</p>