title: Failed to add dependency on mongod.target[Service], ignoring: Invalid argument
body: <p>When I install Rocket.Chat server on CentOS 7, I have created <code>rocketchat.service</code>:</p>
  
  <pre><code>[Unit]
  Description=The Rocket.Chat server
  After=network.target remote-fs.target nss-lookup.target 
  mongod.target[Service]
  Type=simple
  ExecStart=/usr/local/bin/node /opt/Rocket.Chat/main.js
  Restart=always
  StandardOutput=syslog
  StandardError=syslog
  SyslogIdentifier=rocketchat
  User=root
  Environment=MONGO_URL=mongodb://localhost:27017/rocketchat 
  ROOT_URL=http://www.leavenotrace.cn PORT=3000
  [Install] WantedBy=multi-user.target
  </code></pre>
  
  <p>When I pressed on command:</p>
  
  <pre><code>systemctl start rocketchat
  systemctl status rocketchat
  </code></pre>
  
  <p>Show below error:</p>
  
  <pre><code>Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:3] Failed to add dependency on mongod.target[Service], ignoring: Invalid argument
  Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:4] Unknown lvalue 'Type' in section 'Unit'
  Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:5] Unknown lvalue 'ExecStart' in section 'Unit'
  Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:6] Unknown lvalue 'Restart' in section 'Unit'
  Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:7] Unknown lvalue 'StandardOutput' in section 'Unit'
  Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:8] Unknown lvalue 'StandardError' in section 'Unit'
  Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:9] Unknown lvalue 'SyslogIdentifier' in section 'Unit'
  Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:10] Unknown lvalue 'User' in section 'Unit'
  Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:11] Unknown lvalue 'Environment' in section 'Unit'
  Apr 18 11:50:13 VM_56_252_centos systemd[1]: [/etc/systemd/system/rocketchat.service:12] Invalid section header '[Install] WantedBy=multi-user.target'
  </code></pre>