title: failing to start redis server after changing the directory
body: <p>I installed redis using  </p>
  
  <pre><code>sudo apt-get -y install redis-server 
  </code></pre>
  
  <p>The default data directory is /var/lib/redis/, but when I changed to another directory /some path/redisDB in file: sudo gedit /etc/redis/redis.conf, I cannot start the redis sever again. I get an error as </p>
  
  <pre><code>Job for redis-server.service failed because the control process exited with error code. See "systemctl status redis-server.service" and "journalctl -xe" for details.
  
  systemctl status redis-server.service
   redis-server.service - Advanced key-value store
   Loaded: loaded (/lib/systemd/system/redis-server.service; enabled; 
   vendor preset: enabled)
   Active: inactive (dead) (Result: exit-code) since Do 2018-06-14 17:29:03 CEST; 8s ago
   Docs: http://redis.io/documentation,
         man:redis-server(1)
   Process: 18601 ExecStopPost=/bin/run-parts --verbose /etc/redis/redis-server.post-down.d (code=exited, status=0/SUCCESS)
   Process: 18597 ExecStop=/bin/kill -s TERM $MAINPID (code=exited, status=0/SUCCESS)
   Process: 18594 ExecStop=/bin/run-parts --verbose /etc/redis/redis-server.pre-down.d (code=exited, status=0/SUCCESS)
   Process: 18730 ExecStart=/usr/bin/redis-server /etc/redis/redis.conf (code=exited, status=1/FAILURE)
  Process: 18727 ExecStartPre=/bin/run-parts --verbose /etc/redis/redis-server.pre-up.d (code=exited, status=0/SUCCESS)
  Main PID: 18000 (code=exited, status=0/SUCCESS)
  
  Jun 14 17:29:03 gaurav-GB-BSi3-6100 systemd[1]: Failed to start Advanced key-value store.
  Jun 14 17:29:03 gaurav-GB-BSi3-6100 systemd[1]: redis-server.service: Unit entered failed state.
  Jun 14 17:29:03 gaurav-GB-BSi3-6100 systemd[1]: redis-server.service: Failed with result 'exit-code'.
  Jun 14 17:29:03 gaurav-GB-BSi3-6100 systemd[1]: redis-server.service: Service hold-off time over, scheduling restart.
  Jun 14 17:29:03 gaurav-GB-BSi3-6100 systemd[1]: Stopped Advanced key-value store.
  Jun 14 17:29:03 gaurav-GB-BSi3-6100 systemd[1]: redis-server.service: Start request repeated too quickly.
  Jun 14 17:29:03 gaurav-GB-BSi3-6100 systemd[1]: Failed to start Advanced key-value store.
  </code></pre>