Known Issues in Apache ZooKeeper

Technical Service Bulletins

TSB 2022-577: ZooKeeper servers assign similar negative sessionIds to multiple sessions

Each Apache ZooKeeper (“ZooKeeper”) client session has a 64bit long session Id, which must be unique among the online sessions. The clients can connect to any ZooKeeper server and each server assigns the session Id by continuously increasing an “initial session Id” which was set at the start of each ZooKeeper server process.

The bug ZOOKEEPER-1622 would cause:

• Generation of negative ZooKeeper client session Ids causing Apache Accumulo (“Accumulo”) to fail to start
• ZooKeeper client session ID collision on clusters which are heavily using ZooKeeper, resulting in unexpected ZooKeeper session termination or possibly failing ZooKeeper client operations. This may cause unexpected session termination, data inconsistency, or operation failure, among other issues, in downstream services (e.g. HBase service failures, failovers in HA services, etc.)

Upstream JIRA

ZOOKEEPER-1622

Knowledge article

For the latest update on this issue see the corresponding Knowledge article: TSB 2022-577: ZooKeeper servers assign similar negative sessionIds to multiple sessions