title: oservium cannot add_device but can snmpwalk and fping
body: <p>Even after I made sure fping in config same as <code>whereis fping</code> output, I'm still cannot add any device, even localhost.</p>
  
  <p>I also had made sure that snmpwalk successul before running add_device.php</p>
  
  <p>OS: Centos 6 amd64</p>
  
  <pre><code>[root@nms observium]# ./add_device.php -d 127.0.0.1 public v2c 
  DEBUG!
  Observium CE 0.15.6.6430
  Add Device(s)
  
  Wrong process status! Try fix..
  
  CMD[/opt/observium/scripts/distro]
  EXITCODE[0]
  RUNTIME[0.0295s]
  STDOUT[
  Linux|2.6.32-573.8.1.el6.x86_64|amd64|CentOS|6.7
  ]
  
  CMD[/usr/bin/env python --version 2&gt;&amp;1]
  EXITCODE[0]
  RUNTIME[0.039s]
  STDOUT[
  Python 2.6.6
  ]
  
  SQL[SELECT version()]
  RUNTIME[0.01287103s]
  
  CMD[/usr/bin/snmpget --version 2&gt;&amp;1]
  EXITCODE[0]
  RUNTIME[0.0169s]
  STDOUT[
  NET-SNMP version: 5.5
  ]
  
  CMD[/usr/bin/rrdtool --version |head -n1]
  EXITCODE[0]
  RUNTIME[0.0891s]
  STDOUT[
  RRDtool 1.3.8  Copyright 1997-2009 by Tobias Oetiker &lt;tobi@oetiker.ch&gt;
  ]
      Software versions:
    OS:        Linux 2.6.32-573.8.1.el6.x86_64 [amd64] (CentOS 6.7)
    PHP:       5.3.3
    Python:    Python 2.6.6
    MySQL:     5.1.73
    SNMP:      NET-SNMP 5.5
    RRDtool:   1.3.8
  
  Try to add 127.0.0.1:
  
  SQL[SELECT COUNT(*) FROM `devices` WHERE `hostname` = '127.0.0.1']
  RUNTIME[0.04451895s]
  Could not resolve 127.0.0.1.
  Devices failed: 1.
  </code></pre>
  
  <p>Any tips/hints would be great.</p>