Cloudera Docs

Preparing Atlas for upgrade

The Atlas migration exporter utility is used for exporting data from Atlas from HDP 2.6.5.x. You must import this data into the CDP Private Cloud Base version of Atlas.

To estimate the duration for the export operation, use one of the following methods to determine the number of entities in Atlas: The time the tool takes to export the Atlas metadata depends on the number of entities and your cluster configuration.
  • Within Solr, check the number of entities in the vertex_index collection.
  • Run the following Atlas metrics REST API query, with your values for user, password, and Atlas port: 
    curl -g -X GET -u admin:admin -H "Content-Type: application/json"  -H"Cache-Control: no-cache" "http://<atlas_server>:21000/api/atlas/admin/metrics"

If your environment is kerberos enabled, perform the following steps. and proceed to exporting Atlas data.

  1. Switch identity to the Atlas user. $ su - atlas
  2. List the Atlas keytab to find the Atlas Kerberos Service Principal value.
    
$ klist -kt /etc/security/keytabs/atlas.service.keytab
Keytab name: FILE:/etc/security/keytabs/atlas.service.keytab
KVNO Timestamp           Principal
---- ------------------- ------------------------------------------------------
 1 11/28/2018 06:40:24 atlas/finance.acme.trade@ACME.TRADE
 1 11/28/2018 06:40:24 atlas/finance.acme.trade@ACME.TRADE
  3. Initialize the Atlas keytab and the Atlas Kerberos Service Principal value. 
    $ kinit -kt /etc/security/keytabs/atlas.service.keytab atlas/finance.acme.trade@ACME.TRADE
  4. Verify you have a valid ticket.
    $ klist
Ticket cache: FILE:/tmp/krb5cc_1005
Default principal: atlas/finance.acme.trade@ACME.TRADE
Valid starting       Expires              Service principal
11/29/2020 22:52:56  11/30/2020 22:52:56  krbtgt/ACME.TRADE@ACME.TRADE
    renew until 12/06/2020 22:52:56

Export Atlas data:

The Atlas migration exporter utility is used for migrating Atlas from HDP 2.6.5.x to HDP 7.1.x:
  1. In the Ambari Web UI, click Atlas.
  2. Select Actions>Stop.
  3. Ensure that HBase is running. If it is not running, in the Ambari Web UI, click HBase
  4. Select Actions>Start.
  5. SSH to the host where your Atlas Metadata Server is installed.
  6. Download from the location: Atlas migration exporter.
  7. Create this directory mkdir /usr/hdp/2.6.<current version>/atlas/tools/migration-exporter/
  8. Copy the contents to /usr/hdp/2.6.<current version>/atlas/tools/migration-exporter/
  9. Modify the permissions using chown -R atlas:atlas <directory above>
  10. Execute the tool from the location above. atlas_migration.py -d <output directory>. For example, /usr/hdp/2.6.<current version>/atlas/tools/migration-exporter/atlas_migration.py -d /var/lib/atlas-data

    For example, this command exports the metadata to an output directory called atlas_metadata. python /usr/hdp/current/atlas/tools/migration-exporter/atlas_migration_export.py -d ./atlas_metadata

  11. To display the export status, use this command: tail -f /var/log/atlas/atlas-migration-exporter.log.