Apache ZooKeeper 3.5 end of life
Apache ZooKeeper 3.5 reached end of life on 1 June 2022, with 3.5.10 as its final release. It is three lines behind the maintained releases. It remains common because 3.5 was the version bundled with many Kafka, Solr and Hadoop distributions of its era, and those ensembles were rarely revisited.
What now
Which vendors provide Apache ZooKeeper 3.5 security patches now that support has ended?
ZooKeeper EOL: Extended Support for 3.4 to 3.7 (Embedded)- End of life
- 1 June 2022
- Released
- May 2019
- Final release
- 3.5.10
- Successor
- ZooKeeper 3.8 or 3.9
Date published by Apache ZooKeeper release history, cross-checked against endoflife.date. We do not publish a lifecycle date we cannot source. Dates checked on zookeeper.apache.org and endoflife.date on 20 October 2026.
Last reviewed
Apache ZooKeeper versions: release and end-of-life dates
| Version | Released | End of life | Status |
|---|---|---|---|
| Apache ZooKeeper 3.7 | 17 Mar 2021 | 2 February 2024 | End of life |
| Apache ZooKeeper 3.6 | 25 Feb 2020 | 30 December 2022 | End of life |
| Apache ZooKeeper 3.5 (this page) | 3 May 2019 | 1 June 2022 | End of life |
| Apache ZooKeeper 3.4 | 22 Nov 2011 | 1 June 2020 | End of life |
End-of-life dates are published by each project and checked against endoflife.date.
What actually stops on 1 June 2022
- Security fixes for the 3.5 branch and its bundled dependencies
- Any further 3.5.x releases
What actually breaks in the upgrade
3.5 usually arrived bundled, which is why nobody owns it
Ensembles on 3.5 were typically installed as part of a platform distribution rather than chosen. That means no team planned its lifecycle, and the upgrade is often blocked on the platform release that pinned it rather than on ZooKeeper itself.
Your options, costed honestly
Including the ones that do not involve buying anything from us.
| Option | What it is | Effort | Cost | Our view |
|---|---|---|---|---|
| Rolling upgrade to 3.8 or 3.9 | One member at a time, quorum preserved. | Usually stepwise through an intermediate line | Engineering time | The destination, once every client's version tolerance is mapped. |
| OSSeva extended support | Custom 3.5.x builds, scoped per engagement. | Drop-in | Contact us for a quote | Secures the ensemble independently of the platform release that pinned it. |
What OSSeva does for Apache ZooKeeper 3.5
OSSeva patches this line
ZooKeeper 3.5 is custom support, scoped per engagement. It covers patched 3.5.x builds including the bundled Netty, Jetty and logging libraries, with SBOM and VEX evidence for each build.
Apache ZooKeeper extended support
Apache ZooKeeper extended support What your auditor will say
Requires that system components are protected from known vulnerabilities by installing applicable security patches. A release line with no upstream patch stream cannot meet this by itself, whatever the scanner reports.
Vulnerability identification and remediation. Scanning satisfies identification. Remediation is what fails when the fix does not exist for the line you run.
When did ZooKeeper 3.5 reach end of life?
1 June 2022. The final release was 3.5.10. ZooKeeper 3.6 followed on 30 December 2022 and 3.7 on 2 February 2024; only 3.8 and 3.9 remain maintained.
Get a quote
Still running Apache ZooKeeper 3.5?
Tell us the versions and the estate size. We will tell you honestly whether to upgrade or to buy cover — and we say 'upgrade' more often than you would expect.
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