[ZOOKEEPER-2476] Not possible to upgrade via reconfig a Participant+Observer cluster to a Participant+Participant cluster

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Not A Bug
• Affects Version/s: 3.5.1
• Component/s: quorum, server
• Flags: Important
• Assignee: Alexander Shraer
• Reporter: Jordan Zimmerman
• Created: 16/Jul/16 00:25
• Updated: 17/Jul/16 00:21
• Resolved: 17/Jul/16 00:21

Description

Contrary to the documentation, it is not possible to upgrade via reconfig a Participant+Observer cluster to a Participant+Participant cluster. KeeperException.NewConfigNoQuorum is thrown instead.

PrepRequestProcessor should recognize this special case and let it pass. Test will be enclosed shortly. I'll work on a fix as well, but I imagine that shralex will want to look at it.