title: Failed to start firewalld on centos 7
body: <p>I installed firewalld on my centos server but as I tried to start it I got this:</p>
  
  <pre><code>$ sudo systemctl start firewalld
  Job for firewalld.service failed. See 'systemctl status firewalld.service' and 'journalctl -xn' for details.
  </code></pre>
  
  <p>here is the systemctl status:</p>
  
  <pre><code>sudo systemctl status firewalld
  firewalld.service - firewalld - dynamic firewall daemon
     Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled)
     Active: failed (Result: exit-code) since پنجشنبه 2016-04-07 05:36:17 UTC; 9s ago
    Process: 929 ExecStart=/usr/sbin/firewalld --nofork --nopid $FIREWALLD_ARGS (code=exited, status=1/FAILURE)
   Main PID: 929 (code=exited, status=1/FAILURE)
  
  آوریل 07 05:36:17 server1.hamed1soleimani.ir systemd[1]: firewalld.service: main process exited, code=exited, status=1/FAILURE
  آوریل 07 05:36:17 server1.hamed1soleimani.ir systemd[1]: Failed to start firewalld - dynamic firewall daemon.
  آوریل 07 05:36:17 server1.hamed1soleimani.ir systemd[1]: Unit firewalld.service entered failed state.
  </code></pre>
  
  <p>and firewall-cmd status:</p>
  
  <pre><code>sudo firewall-cmd --stat
  Traceback (most recent call last):
    File "/bin/firewall-cmd", line 24, in &lt;module&gt;
      from gi.repository import GObject
    File "/usr/lib64/python2.7/site-packages/gi/__init__.py", line 37, in &lt;module&gt;
      from . import _gi
  ImportError: /usr/lib64/python2.7/site-packages/gi/_gi.so: undefined symbol: g_type_check_instance_is_fundamentally_a
  </code></pre>
  
  <p>I cant realize relation between firewalld and some gtk python extensions!</p>