title: Grep all IP address from nslookup
body: <p>I'd like to get all IP of google netblock.</p>
  
  <pre><code>[root@ip-10-0-7-131 ~]# nslookup -q=TXT _netblocks.google.com 8.8.8.8 | grep 'ip4'
  </code></pre>
  
  <p>Here's result: </p>
  
  <pre><code>_netblocks.google.com   text = "v=spf1 ip4:64.233.160.0/19 ip4:66.102.0.0/20 ip :66.249.80.0/20 ip4:72.14.192.0/18 ip4:74.125.0.0/16 ip4:108.177.8.0/21 ip4:173.194.0.0/16 ip4:209.85.128.0/17 ip4:216.58.192.0/19 ip4:216.239.32.0/19 ~all"
  </code></pre>
  
  <p>But my expected result is:</p>
  
  <pre><code>64.233.160.0/19
  66.102.0.0/20
  ........
  </code></pre>
  
  <p>How can i achieve my goal?</p>
  
  <p>My best effort is only get 1 IP :(</p>
  
  <pre><code>[root@ip-10-0-7-131 ~]# nslookup -q=TXT _netblocks.google.com 8.8.8.8 | grep 'ip4' | cut -d: -f3 | awk '{print $1}'
  66.102.0.0/20
  </code></pre>