title: Is it OK to fsfreeze --unfreeze directly after create-snapshot returns?
body: <p>Assume <em>/data</em> is the mount point for an EXT4 file system that occupies a whole EBS volume.
  To create a backup, the file system is freezed and a snapshot is created.</p>
  
  <pre><code>root@ubuntu:~# fsfreeze --freeze /data
  root@ubuntu:~# aws ec2 create-snapshot --volume-id vol-1234567 --description "/data snapshot"
  {
      "SnapshotId": "snap-27c5ebdf",
      "Description": "/data snapshot",
      "VolumeId": "vol-1234567",
      "State": "pending",
      "VolumeSize": 250,
      "OwnerId": "744275636941",
      "StartTime": "2014-11-04T15:17:19.000Z",
      "Tags": []
  }
  root@ubuntu:~#
  </code></pre>
  
  <p>Is it at this point OK to run</p>
  
  <pre><code>root@ubuntu:~# fsfreeze --unfreeze /data
  </code></pre>
  
  <p>and start writing files under <em>/data</em>?</p>
  
  <p>In other words, is it OK to start using an EBS volume directly after <code>aws ec2 create-snapshot</code> returns, although the state of the snapshot might be <strong>pending</strong>?</p>