[SOLR-7989] After a new leader is elected it, it should ensure it's state is ACTIVE if it has already registered with ZK.

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 5.4, 6.0
• Assignee: Mark Miller
• Reporter: Ishan Chattopadhyaya
• Created: 29/Aug/15 03:32
• Updated: 09/May/16 18:56
• Resolved: 13/Nov/15 22:03

Description

It is possible that a down replica gets elected as a leader, and that it stays down after the election.

Here's how I hit upon this:

• There are 3 replicas: leader, notleader0, notleader1
• Introduced network partition to isolate notleader0, notleader1 from leader (leader puts these two in LIR via zk).
• Kill leader, remove partition. Now leader is dead, and both of notleader0 and notleader1 are down. There is no leader.
• Remove LIR znodes in zk.
• Wait a while, and there happens a (flawed?) leader election.
• Finally, the state is such that one of notleader0 or notleader1 (which were down before) become leader, but stays down.

Issue Links

• is depended upon by: SOLR-7569 Create an API to force a leader election between nodes