title: Which is the best approach to migrate DateFlows after NiFi Upgraded?
body: <p>As the title suggests,after Nifi-1.9.2 was upgraded to Nifi-1.10.0,i found there are three approaches to migrate DFs are as follows:</p>
  
  <p>1.Using template</p>
  
  <p>2.Importing DF from Nifi registry</p>
  
  <p>3.Loading the copied flow.xml.gz file from old version</p>
  
  <p>WHICH IS THE BEST APPROACH?Thanks in advance!</p>