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• If you want to suppress errors in INSERT (be careful with this though), use INSERT IGNORE as opposed to INSERT. We mostly use it when have to insert global config variable missing in just some of the previous releases:       

  No Format
  INSERT IGNORE INTO `cloud`.`configuration` VALUES ('Advanced', 'DEFAULT', 'management-server', 'direct.agent.load.size', '16', 'The number of direct agents to load each time');

•  Never modify the upgrade path leading to the version that is already released, unless its a blocker bug and the customer needs a patch. Example: 4.1 was released, and there is a bug in 4.0->4.1 upgrade path. The fix should be made in 4.1->4.2 patch, never in 4.0->4.1

Known issues

• No rollback is supported. We always insist on saving the DB dump before running the upgrade so in case something goes wrong, the Admin can do manual rollback. Steps to do the manual rollback:
  
  

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