@Vishal Gupta Would always advise to review the documentation on the Ambari and HDP upgrade. Generally, no, you don't need to re-gen all of the keytabs or SSL in the cluster as part of an upgrade - though Ambari will generate keytabs as required post-upgrade. https://docs.hortonworks.com/HDPDocuments/Ambari-2.4.2.0/bk_ambari-upgrade/content/upgrading_HDP_post_upgrade_tasks_ranger_kerberos.html There are certain cases which need some attention (e.g. Kafka at 2.2, Ranger HA, etc.). https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.5.0/index.html You can raise a ticket with Hortonworks Support prior to the upgrade, as they can inform you on any known issues (if you have a subscription). Also, would recommend to move to 2.5.5 if moving to 2.5. And testing is imperative. Would advise to test all of the components under representative use cases.
... View more
