[CURATOR-696] Double leader for LeaderLatch

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 5.4.0, 5.5.0
• Fix Version/s: 5.7.0
• Assignee: Zili Chen
• Reporter: lurna
• Created: 18/Dec/23 01:42
• Updated: 19/Aug/24 08:39
• Resolved: 21/May/24 14:59

Description

When I use the LeaderLatch to select leader, there is a double-leader phenomenon.
The timeline is as follows：

1.A client connected and set its leader status to true

2.zk offline until the session with the A client expires

3.zk online，A client Reconnected and set its leader status to true with old path

4.zk delete old path（A client）because of expires

5.A client cannot perceive that its node has been deleted，continues to believe that it is the leader

6.B client connected，due to zk's node being empty, set its leader status to true

7.now A client and B client are the leader at the same time
 
It seems that due to CURATOR-644 and CURATOR-645

Issue Links

• fixes: CURATOR-620 Double Leadership Issue while using Leader Latch Recipe
• links to: GitHub Pull Request #500
• links to: GitHub Pull Request #16444