One of our customer has questions about the rolling upgrade mechanism that they are planning to use for delivering small fixes to our systems in the field. The context: They are going to be delivering patches using their internal patch processes. This patch process includes the ability to ‘apply’ and also ‘remove’ patches. They were thinking of leveraging the Ambari Rolling Upgrade for the ‘apply’ mechanism for HDP distribution patches, but there may be some issues on the ‘remove’ patch mechanism. The issue: At the end rolling upgrade there is a decision point to ‘Finalize’, ‘Finalize Later’, or ‘Downgrade’ the upgrade. The context of the question is the web page: http://docs.hortonworks.com/HDPDocuments/Ambari-2.1.0.0/bk_upgrading_Ambari/content/_performing_the_upgrade_rmiu.html If they are going to support the removal of patches, they would need to select the ‘Finalize Later’ option for the rolling upgrade. However, the Note at the bottom of the web page indicates that the current version is the ‘starting version’, as well, they won’t be able to make configuration changes while in the ‘Finalize later’ state. This likely won’t work for them as on restarts of the Name Node and/or the other nodes in the cluster, they will need to have the patched software started by default. Also, once a patch operation is done (from thier point of view), they would need to be able to make configuration changes. So, if they use ‘Finalize’ to finish the patch operation, according to the above web page, they would lose the ability to ‘downgrade’ the patched content back to the starting version. If there is no way to go back to the ‘starting version’, they will not be able to utilize the rolling upgrade approach. What they are wondering is if there is a way to perform an “upgrade in reverse” after performing the ‘finalize’. Perhaps set things up to re-install the ‘starting version’ rpms and set up the respositories to utilize those pre-first-upgrade versions. Is this a viable option for them? Do we have anything better that they would be able to use? ... View more

Oozie Database size is growing at a rapid pace. It is currently @ 22gb but the customer would like to know how to limit the size of this db? and also looking for a procedure to archive old data so that it will never run of the space allocated. Can someone point me in the right direction to address this customer's concerns on Oozie Database size? ... View more

Do we support HA for History and Timeline Server? if either of these services is down, is there any impact to hadoop services? what is the impact if they are down for couple of hours. please advise. ... View more

Our customer would like to see Ambari alerts integrated with their fault management system via SNMP. So they have the following questions. Could someone please take a look at these questions and let me know how we can address them? What is the Ambari MIB for alerts via SNMP? Any recommendations on OIDs? Do we have a list of custom properties that can be configured for the MIB via Ambari? ... View more

I see the following option to export one table at a time but do we have a way to do this for all the tables on a particular hive db? EXPORT TABLE tablename [PARTITION (part_column= "value" [, ...])] TO 'export_target_path' ... View more

Can someone help me to fetch service level config using ambari REST API? For example, we would like to have the following config value pulled using ambari REST API calls. hive.server2.transport.mode hive.txn.timeout Thanks, ... View more