This is the documentation for CDH 5.1.0.
Documentation for other versions is available at Cloudera Documentation.

Known Issues Fixed in CDH 5.0.1

The following topics describe known issues fixed in CDH 5.0.0.

Apache Hadoop

HDFS

— NameNode LeaseManager may crash

Bug: HDFS-6148/HDFS-6094

Severity: High

Workaround: Restart the NameNode.

— Some group mapping providers can cause the NameNode to crash

In certain environments, some group mapping providers can cause the NameNode to segfault and crash.

Bug: HADOOP-10442

Severity: High

Workaround: Configure either ShellBasedUnixGroupsMapping in Hadoop or configure SSSD in the operating system on the NameNode.

Apache Hive

— CREATE TABLE AS SELECT (CTAS) does not work with Parquet files

Since CTAS does not work with Parquet files, the following example will return null values.
CREATE TABLE test_data(column1 string); 
LOAD DATA LOCAL INPATH './data.txt' OVERWRITE INTO TABLE test_data; 

CREATE TABLE parquet_test 
ROW FORMAT SERDE 'parquet.hive.serde.ParquetHiveSerDe' 
   STORED AS 
    INPUTFORMAT 'parquet.hive.DeprecatedParquetInputFormat' 
    OUTPUTFORMAT 'parquet.hive.DeprecatedParquetOutputFormat' 
   AS 
     SELECT column1 FROM test_data; 

SELECT * FROM parquet_test; 
SELECT column1 FROM parquet_test;

Bug: HIVE-6375

Severity: Medium

Workaround: A workaround for this is to follow up a CREATE TABLE query with an INSERT OVERWRITE TABLE SELECT * as in the example below.
CREATE TABLE parquet_test (column1 string)
ROW FORMAT SERDE 'parquet.hive.serde.ParquetHiveSerDe'
  STORED AS
   INPUTFORMAT 'parquet.hive.DeprecatedParquetInputFormat'
   OUTPUTFORMAT 'parquet.hive.DeprecatedParquetOutputFormat';
INSERT OVERWRITE TABLE parquet_test SELECT * from test_data;

Apache Oozie

— The oozie-workflow-0.4.5 schema has been removed

Workflows using schema 0.4.5 will no longer be accepted by Oozie because this schema definition version has been removed.

Bug: OOZIE-1768

Severity: Low

Workaround: Use schema 0.5. It's backwards compatible with 0.4.5, so updating the workflow is as simple as changing the schema version number.