anchor.diff:      gpadmin@gp6master$ pxf cluster sync
       ```
    
  -6. Start PXF on each Greenplum Database 6 segment host as described in [Starting PXF](../../pxf/5-15/cfginitstart_pxf.html#start_pxf).
  +6. Start PXF on each Greenplum Database 6 segment host:
  +
  +    ``` shell
  +    gpadmin@gp6master pxf cluster start
  +    ```
   
   7. Verify the migration by testing that each PXF external table can access the referenced data store.
   
  
positive.code: 
  - Identify the version number of your Greenplum 5 installation. If it is older than 5.21.2, upgrade to a newer 5.x version.
  - Identify the version of PXF running in the Greenplum 5 cluster.
  - Determine if you have `gphdfs` external tables defined in your Greenplum 5 installation.
  - Identify the file system location of the PXF `$PXF_CONF` directory in your Greenplum 5 installation. In Greenplum 5.15 and later, `$PXF_CONF` identifies the user configuration directory that was provided to the `pxf cluster init` command. This directory contains PXF server configurations, security keytab files, and log files.
  
  
  ## <a id="pxf5pre"></a>Step 1: Complete PXF Greenplum Database 5 Pre-Migration Actions
  
negative.code:     gpadmin@gp6master$ scp -r gpadmin@<gp5master>:/usr/local/greenplum-pxf /usr/local/
      ```
  
  3. Initialize PXF on each segment host as described in [Initializing PXF](../../pxf/5-16/init_pxf.html), specifying the `PXF_CONF` directory that you copied in the step above.
  
  5. **If you are migrating PXF from Greenplum Database version 5.23 or earlier** and you have configured any JDBC servers that access Kerberos-secured Hive, you must now set the `hadoop.security.authentication` property in the `jdbc-site.xml` file to explicitly identify use of the Kerberos authentication method. Perform the following for each of these server configs:
  
      1. Navigate to the server configuration directory.
      2. Open the `jdbc-site.xml` file in the editor of your choice and uncomment or add the following property block to the file:
  
          ```xml
          <property>
              <name>hadoop.security.authentication</name>
              <value>kerberos</value>
          </property>
          ```
      3. Save the file and exit the editor.
  
  5. **If you are migrating PXF from Greenplum Database version 5.26 or earlier**: The PXF `Hive` and `HiveRC` profiles now support column projection using column name-based mapping. If you have any existing PXF external tables that specify one of these profiles, and the external table relied on column index-based mapping, you may be required to drop and recreate the tables:
  
      1. Identify all PXF external tables that you created that specify a `Hive` or `HiveRC` profile.
  
      2. For *each* external table that you identify in step 1, examine the definitions of both the PXF external table and the referenced Hive table. If the column names of the PXF external table *do not* match the column names of the Hive table:
  
          1. Drop the existing PXF external table. For example:
  
              ``` sql
              DROP EXTERNAL TABLE pxf_hive_table1;
              ```
  
          2. Recreate the PXF external table using the Hive column names. For example:
  
              ``` sql
              CREATE EXTERNAL TABLE pxf_hive_table1( hivecolname int, hivecolname2 text )
                LOCATION( 'pxf://default.hive_table_name?PROFILE=Hive')
              FORMAT 'custom' (FORMATTER='pxfwritable_import');
              ```
  
          3. Review any SQL scripts that you may have created that reference the PXF external table, and update column names if required.
  
  5. Synchronize the PXF configuration from the Greenplum Database 6 master host to the standby master and each segment host in the cluster. For example:
  
  