Ozone 2.1.0 JDK compatibility

[dishtik]

Hello Ozone community,

I am testing a bare-metal single-node non-HA deployment of Ozone 2.1.0 and noticed a possible mismatch in the documented JDK compatibility versus the behavior of the Ansible-based installation flow.

According to the Ozone 2.1.0 bare-metal installation documentation:
Manual installation prerequisites mention support for JDK 11 / JDK 17
Reference:
https://ozone.apache.org/docs/quick-start/installation/bare-metal/
However, when using the Ansible-based installation flow (ozone-installer.py / ansible-playbook), it appears that the playbook provisions Ozone with JDK 17 or JDK 21.

I used the Ansible ozone-installer.py flow for a single-node non-HA deployment and explicitly provided JDK major version = 11
The Ozone services came up successfully, so at first glance the deployment looked fine. However, a basic validation step — simple data ingestion is failing due to java lang class introduced in Java 12.

Could anyone help me clarify the intended JDK support matrix for Ozone 2.1.0?

1. Is JDK 11 officially supported for Ozone 2.1.0 in both manual bare-metal installation, and Ansible-based deployment?
2. If JDK 11 is no longer fully supported (or only partially supported), should the documentation be updated to reflect the actual supported versions?

Log trace:

# bin/ozone sh key put /vol1/bucket1/key1 /tmp/test.txt
Picked up JAVA_TOOL_OPTIONS:  --add-opens=java.base/jdk.internal.misc=ALL-UNNAMED --add-opens=java.base/java.lang.reflect=ALL-UNNAMED --add-opens=java.base/java.nio=ALL-UNNAMED --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.util=ALL-UNNAMED
...
2026-03-17 15:29:09,988 [main] DEBUG ha.OMFailoverProxyProviderBase: RetryProxy: OM om1: RemoteException: java/lang/constant/Constable
	at org.apache.hadoop.ozone.om.ratis.utils.OzoneManagerRatisUtils.createClientRequest(OzoneManagerRatisUtils.java:353)
	at org.apache.hadoop.ozone.om.execution.OMExecutionFlow.submitExecutionToRatis(OMExecutionFlow.java:62)
	at org.apache.hadoop.ozone.om.execution.OMExecutionFlow.submit(OMExecutionFlow.java:54)
	at org.apache.hadoop.ozone.protocolPB.OzoneManagerProtocolServerSideTranslatorPB.internalProcessRequest(OzoneManagerProtocolServerSideTranslatorPB.java:174)
	at org.apache.hadoop.ozone.protocolPB.OzoneManagerProtocolServerSideTranslatorPB.processRequest(OzoneManagerProtocolServerSideTranslatorPB.java:124)
	at org.apache.hadoop.hdds.server.OzoneProtocolMessageDispatcher.processRequest(OzoneProtocolMessageDispatcher.java:89)
	at org.apache.hadoop.ozone.protocolPB.OzoneManagerProtocolServerSideTranslatorPB.submitRequest(OzoneManagerProtocolServerSideTranslatorPB.java:115)
	at org.apache.hadoop.ozone.protocol.proto.OzoneManagerProtocolProtos$OzoneManagerService$2.callBlockingMethod(OzoneManagerProtocolProtos.java)
	at org.apache.hadoop.ipc.ProtobufRpcEngine$Server.processCall(ProtobufRpcEngine.java:484)
	at org.apache.hadoop.ipc.ProtobufRpcEngine2$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine2.java:595)
	at org.apache.hadoop.ipc.ProtobufRpcEngine2$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine2.java:573)
	at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:1228)
	at org.apache.hadoop.ipc.Server$RpcCall.run(Server.java:1246)
	at org.apache.hadoop.ipc.Server$RpcCall.run(Server.java:1169)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/javax.security.auth.Subject.doAs(Subject.java:423)
	at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1953)
	at org.apache.hadoop.ipc.Server$Handler.run(Server.java:3198)
Caused by: java.lang.ClassNotFoundException: java.lang.constant.Constable
	at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
	at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:527)
	... 18 more

[adoroszlai]

Ozone is built for minimum JDK 8, so it should work with JDK 11. ozone-installer is a new project, not officially supported. @ssulav may be able to help.

[ssulav]

Yes, ozone-installer as a new project had support added only for jdk17 and jdk21 as defaults. Do we have an official certified list of java support matrix for all ozone released versions? If not, we should dedicate a page in docs for the support matrix. We can later use and implement the same in the deployer too. Thanks, Soumitra

…

On Wed, 18 Mar 2026 at 1:32 AM, Doroszlai, Attila ***@***.***> wrote: Ozone supports running with JDK 8. ozone-installer is a new project, not officially supported. @ssulav <https://github.com/ssulav> may be able to help. — Reply to this email directly, view it on GitHub <#9934 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AJVRDOUFKB5K377AXYVBXJT4RGVO7AVCNFSM6AAAAACWUPAM5GVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTMMJYGMYTGMA> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[dishtik]

@adoroszlai @ssulav Thank you for the clarification that Ozone 2.1.0 supports JDK 8 and JDK 11.

Based on that, I revalidated the setup using a manual installation from the Ozone 2.1.0 tarball, strictly following the bare-metal installation documentation, and ensured the environment is running on JDK 11. However, I am still seeing the same runtime failure during a basic data ingestion test.

RemoteException: java/lang/constant/Constable at org.apache.hadoop.ozone.om.ratis.utils.OzoneManagerRatisUtils.createClientRequest(OzoneManagerRatisUtils.java:353)
The class/interface java.lang.constant.Constable was introduced in Java 12.
That suggests that, although Ozone 2.1.0 services may start successfully on JDK 11, at least this code path appears to reference a Java 12+ API during runtime.

Please let me know if I'm missing anything.

[adoroszlai]

Thanks @dishtik for checking, managed to reproduce this, will check.

[adoroszlai]

Created HDDS-14858.

[adoroszlai]

Proposed fix in #9945.