Release Notes
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Known Issues

Hortonworks Bug IDApache JIRAApache ComponentSummary

Description of Problem: The hbck repair tool sometimes generates local indexes that are inconsistent with table data when overlapping regions are encountered.

Workaround: If you know the database schema, fix this issue by dropping and recreating all local indexes of the table after the hbck tool completes operation. Alternatively, rebuild the local indexes using the following ALTER query:

ALTER INDEX IF EXISTS index_name ON data_table_name REBUILD

BUG-60904 KNOX-823 Knox

Description of Problem: When Apache Knox uses Ambari as a proxy, the QuickLinks are not rewritten to go back through the gateway.

Workaround: If all access to Ambari is through Knox in the deployment the new Ambari quicklink profile may be used to hide and/or change URLs to go through Knox permanently. A future release will make these reflect the gateway appropriately.

BUG-60904 KNOX-823 Knox

Description of Problem: When Ambari is being proxied by Apache Knox the QuickLinks are not rewritten to go back through the gateway.

Workaround: If all access to Ambari is through Knox, the new Ambari quicklink profile may be used to hide and/or change URLs to go through Knox permanently. Future release will make these reflect the gateway appropriately.

BUG-65977 SPARK-14922 Spark

Description of Problem: Since Spark 2.0.0, `DROP PARTITION BY RANGE` is not supported grammatically. In other words, only '=' is supported while `<', '>', '<=', '>=' aren't.

Associated Error Message:

scala> sql("alter table t drop partition (b<1) ").show 
mismatched input '<' expecting {')', ','}(line 1, pos 31)

== SQL == 
alter table t drop partition (b<1) 

Workaround: To drop partition, use the exact match with '='. scala> sql("alter table t drop partition (b=0) ").show

BUG-65977 SPARK-14922 Spark

Description of Problem: Since Spark 2.0.0, `DROP PARTITION BY RANGE` does not support relative logical operators. In other words, only '=' is supported while `&lt;', '&gt;', '&lt;=', '&gt;=' are not.

Error Message:

scala&gt; sql().show
mismatched input }(line 1, pos 31)

== SQL ==
alter table t drop partition (b&lt;1)

Workaround: To drop partition, use the exact match with '='.

scala&gt; sql().show

Description of Problem: A Hive query submitted to the %jdbc interpreter returns a proxy validation error.

Associated error messages:

  • HiveSQLException: Failed to validate proxy privilege of zeppelin for <user>

  • The hiveserver2.log file lists a permission denied exception: org.apache.hadoop.ipc.RemoteException( Permission denied: user=<user>, access=WRITE, inode="/user/<user>":hdfs:hdfs:drwxr-xr-x at org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.check( …


  1. Create the user account on all worker nodes. For example, if the account is user3, issue the following command: $ adduser user3

  2. Restart the %jdbc interpreter.


Description of Problem: When used with Hive, the %jdbc interpreter might require Hadoop common jar files that need to be added manually.


  1. On the Interpreters page, add a new repository.

  2. Set the repository ID to “hortonworks”.

  3. Set the URL to “”.

  4. Identify the version of HDP running on the cluster. You can find this in the Zeppelin UI by clicking on your user ID and choosing "About Zeppelin." The number after the Zeppelin version is the HDP version number.

  5. In the Dependencies section on the Interpreters page, remove existing jar files and add the following three jar files, with the correct HDP version for your cluster. The following example uses version

    • org.apache.hive:hive-jdbc::standalone:1.2.1000. Xerces:xerces:2.4.0

    • org.apache.hadoop:hadoop-common:

BUG-74152 PHOENIX-3688 Phoenix

Description of Problem: Rebuild(ALTER INDEX IDX ON TABLE REBUILD) of indexes created on the table having row_timestamp column will result in no data visible to the User for that Index.

Workaround: Drop the index and recreate the same index. There will not be any extra overhead of recreating index when compared with rebuild Index.

BUG-75179 ZEPPELIN-2170 Zeppelin

Description of Problem: Zeppelin does not show all WARN messages thrown by spark-shell. The log level that comes as output at the Zeppelin notebook level cannot be changed .

Workaround: Currently, there is no known workaround.

BUG-76996N/ASpark 2 (Livy)

Description of Problem: When upgrading from HDP-2.5.x to HDP-2.6.0 and using Spark2, the Livy interpreter is configured with a scope of 'global', and should be changed to 'scoped'.

Workaround: After upgrading from HDP 2.5 to HDP 2.6, set the interpreter mode for %livy (Spark 2) to "scoped" using the pulldown menu in the %livy section of the Interpreters page.


Description of problem: "ValueError: No JSON object could be decoded" when restarting Zeppelin, when the disk is 100% full.

Associated error message: Get following in error logs

Traceback (most recent call last): 
File , line 312, in &lt;module&gt; 
File , line 280, in execute 
File , line 182, in start 
File , line 232, in update_kerberos_properties 
config_data = self.get_interpreter_settings() 
File , line 207, in get_interpreter_settings 
config_data = json.loads(config_content) 
File , line 339, in loads 

Workaround: Free up some space in disk, then delete /etc/zeppelin/conf/*.json, then restart zeppelin server


Component Affected: Ranger, all

Description of Problem: SSL is deprecated; its use in production is not recommended. Use TLS.

Workaround: For Ambari: Use ssl.enabled.protocols=TLSv1|TLSv1.1|TLSv1.2 and security.server.disabled.protocols=SSL|SSLv2|SSLv3. For help configuring TLS for other components, contact customer support. Documentation will be provided in a future release.

BUG-80656 Zeppelin

Description of Problem: Zeppelin fails to start during the upgrade process from HDP 2.5 to HDP 2.6. The error starts with

Exception in thread "main" org.apache.shiro.config.ConfigurationException: Unable to instantiate class org.apache.zeppelin.server.ActiveDirectoryGroupRealm for object named 'activeDirectoryRealm'. Please ensure you've specified the fully qualified class name correctly.

Workaround: This error is due to a change in configuration class for Active Directory.

In HDP 2.5:


In HDP 2.6:


To resolve this issue, choose one of the following two alternatives:

  • Proceed with the upgrade, and change the configuration in the shiro.ini file after the upgrade is complete (when Ambari allows configuration change).

  • At time of failure, change the class name in /usr/hdp/current/zeppelin-server/conf/shiro.ini, and then start Zeppelin manually.


Component Affected: Zeppelin/Livy

Description of Problem: This occurs when running applications through Zeppelin/Livy that requires 3rd-party libraries. These libraries are not installed on all nodes in the cluster but they are installed on their edge nodes. Running in yarn-client mode, this all works as the job is submitted and runs on the edge node where the libraries are installed. In yarn-cluster mode,this fails because the libraries are missing.

Workaround: Set the location inspark.jars in spark-defaults.conf. For Livy, you will need to set livy.spark.jars (the HDFS location) in livy interpreters conf. Both are globally applicable. The jars need to be present on the livy machine in both cases. Updating livy conf is preferable since it affects only the Zeppelin users.


Description of Problem: Executing concurrent queries over Spark via Spark1-llap package spawns multiple threads. This may cause multiple queries to fail. However, this will not break the spark thrift server. Spark 1.6 is built using Scala 2.10, which is where this issue manifests (i.e. " synchronize reflection code as scala 2.10 reflection is not threadsafe self"). This issue was subsequently fixed in Scala 2.11 based on this patch

Associated error messages:

  • scala.reflect.internal.Symbols$CyclicReference: illegal cyclic reference involving class LlapContext
  • SparkExecuteStatementOperation: Error running hive query: 
    org.apache.hive.service.cli.HiveSQLException: scala.reflect.internal.Symbols$CyclicReference: illegal cyclic reference involving class LlapContext

Workaround: Isolate the broken queries and re-run them one by one. This will limit the query to one spawned thread.


Description of Problem: After upgrading from Ambari 2.4.2 to Ambari 2.5.2 and subsequent HDP stack upgrade from 2.5 to 2.6, jdbc(hive) interpreter fails to work correctly in Zeppelin.

Associated Error Message: You might see one of the following errors in the Zeppelin stacktrace after running jdbc(hive):

  • Error in doAs

  • Failed to validate proxy privilege of zeppelin


  1. Make sure hadoop.proxyuser.zeppelin.groups=* and hadoop.proxyuser.zeppelin.hosts=* are set in HDFS core-site.xml. If not, then configure these properties and restart all stale services. (AMBARI-21772 is currently tracking this item).

  2. Make user hive.url is configured correctly in Zeppelin's JDBC hive interpreter.


    The URL configured might be wrong, especially on secured and/or wire-encrypted clusters, due to a known issue that we will address in a future release.

  3. Restart HS2.


Since Mahout is deprecated in favor of Spark ML, and every code change carries the risk of creating additional incompatibilities, we will document these difficulties rather than change these established behaviors in Mahout. These issues affect only Mahout.

  • BUG-80945: Potential DoS vulnerability due to ReadLine usage in 9 files

  • BUG-80944: Potential JavaScript vulnerability in

  • BUG-80942: Potential Path Manipulation vulnerability due to path input usage in 8 files

  • BUG-80941: Potential DoS vulnerability due to StringBuilder usage in

  • BUG-80940: Potential DoS vulnerability due to ReadLine usage in 8 additional files

  • BUG-80938: Potential invalid use of Object.equals in and


Description of Problem: RDMBS schema for Hive metastore contains an index HL_TXNID_INDEX defined as


Hash indexes are not recommended by Posgres. Details can be found in

Workaround: It's recommended that this index is changed to type BTREE.


Description of Problem: Router is an optional component in Druid deployment. If the router component of Druid is deployed on a cluster with Kerberos security, Hive queries on Druid tables sometimes fail.

Workaround: If you want to use the optional router component, then ensure that it is hosted on a broker node.

BUG-91304 HIVE-18099 Ambari, Hive, MapReduce, Tez

Description of problem: Running Hive with Tez fails to load configured native library. For example, Snappy compression library.

Associated error message:

 java.lang.RuntimeException: Unable to get CompressorType for codec ( This is most likely due to missing native libraries for the codec.

Workaround: Add the configuration parameter mapreduce.admin.user.env to tez-site.xml, specifying the native library path. For example,

BUG-91364 AMBARI-22506 Zeppelin

Description of problem: The pie chart does not display the correct distribution as per data. This occurs when there is a "," in data i.e. there is number formatting applied to data.

Associated error message: No error message.

Workaround: A manual config in Zeppelin's JDBC interpreter setting, i.e. to add "phoenix.phoenix.query.numberFormat" with value "#.#".

BUG-91996LIVY-299Livy, Zeppelin

Description of Problem: Livy Spark interpreter will only print out the last line of code in the output. For example, if you submit the following:


Livy will only print "11" and ignore the first line.

Workaround: If you want to see the output of a particular line, it must be the last line in the code block in a para.

BUG-92483 HIVE-17900 Hive

Description of Problem: Compaction of ACID table might fail if table is partitioned by more than one column.

Associated Error message: Could not update stats for table ...

Workaround: Currently, there is no known workaround for this issue.

BUG-92957 HIVE-11266 Hive

Description of Problem: Hive returns the wrong count result on an external table with table statistics if you change table data files.

Workaround: Currently, there is no known workaround for this issue.


HSI (Hive2) is not affected.


Description of Problem: The log4j version used in this release can occasionally lead to a failed query or a failure of an LLAP daemon. This is caused by a race condition in the library and can result in a ConcurrentModificationException.

LLAP daemons are restarted transparently by the system. However, the system will log queries that cannot recover as failed.

Workaround: Re-run the query to resolve the problem.

RMP-7861 HBASE-14138 HBase

Description of Problem: Only an hbase superuser can perform HBbase backup-and-restore.