[ZOOKEEPER-2888] Reconfig Command Isolates One of the Nodes when All Ports Change

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 3.5.3
• Component/s: quorum
• Assignee: Unassigned
• Reporter: Cesar Stuardo
• Created: 01/Sep/17 19:52
• Updated: 01/Sep/17 19:59

Description

When we run our Distributed system Model Checking (DMCK) in ZooKeeper v3.5.3 by following the workload (complete details attached):

1. start a 5 node cluster (all nodes know each other).
2. wait for the cluster to reach a steady state.
3. issue reconfig command which does not add or remove nodes but changes all the ports of the existing cluster (no role change either).

We observer that in some situations, one of the followers my end up isolated since the other nodes change their ports and end up setting up new connections. The consequence is similar to the one at ZK-2865 but the scenario is different.

We provide further details in the attached document.