I recreated an HBase service on one of my clusters and on start received a TableExistsException error: Error: org.apache.hadoop.hbase.master.TableNamespaceManager Namespace table not found. Creating… Jul […]
Continue readingCategory: Cloudera Manager
HBase: RowCount Script
I wrote a quick script to count all rows in all tables in HBase. This works great for my Dev clusters that have ever-growing tables […]
Continue readingHDFS JournalNode: JournalNotFormattedException: Journal Storage Directory * not formatted
I woke up to an alert from our Cloudera Manager managed Hadoop cluster: Error: Aug 15, 2:46:01.285 PM WARN org.apache.hadoop.security.UserGroupInformation PriviledgedActionException as:hdfs (auth:SIMPLE) cause:org.apache.hadoop.hdfs.qjournal.protocol.JournalNotFormattedException: Journal […]
Continue readingHDFS Under Replicated Blocks
This is an HDFS service-level health check that checks that the number of under-replicated blocks does not rise above some percentage of the cluster’s total […]
Continue readingDelete a Kafka Topic
Typical delete command: kafka-topics –zookeeper zk_host:port/chroot –delete –topic my_topic_name The topic will be “marked for deletion” and should be removed soon. What happens is an /admin/delete_topics/<topic> node […]
Continue readingCopy data from one Hadoop cluster to another Hadoop cluster (running different versions of Hadoop)
I had to copy data from one Hadoop cluster to another recently. However, the two clusters ran different versions of Hadoop, which made using distcp […]
Continue readingSqoop Server Startup Failure: Upgrade required but not allowed
After an upgrade from CDH 5.0.2 to CDH 5.0.3, Sqoop failed to start with the following error: Server startup failure, Connector registration failed, Upgrade required […]
Continue readingHBase All Regions in Transition: state=FAILED_OPEN
After I added a jar file to the HBase Master I had a problem where regions failed to transition to a RegionServer. Below are the errors; […]
Continue readingCloudera Manager HBase Check HFile Version
An under-documented feature in Cloudera Manager is the HBase Check HFile Version. When upgrading from CDH 4.7 to CDH 5.0, I ran across the instructions that […]
Continue readingCannot Start HBase Master: SplitLogManager: Error Splitting
I could not start HBase within Cloudera Manager, the service reported errors. I was initially confused because I could start the Master when the RegionServers […]
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