Knowledge is Power
At times some directories on hdfs has too many inodes (files and folders) and it is really hard to delete. Some instances also lead to out of memory (OOM) errors such as the following error, INFO retry.RetryInvocationHandler: java.io.IOException: com.google.protobuf.ServiceException: java.lang.OutOfMemoryError:...
Querying hive metastore tables can provide more in depth details on the tables sitting in Hive. This article is a collection of queries that probes Hive metastore configured with mysql to get details like list of transactional tables, etc. More...
Got in a situation where you were asked to extract hive queries and the time they took to execute? Steps On log files run below 2 extracts awk ‘match($0, “^([^ ]+).*Completed executing command\\(queryId=([0-9a-z_-]+)\\); Time taken: (.*)”, a) {print “COMPLETE\t” a[1]...
Lookup yarn queue of a user from bash This bash function will lookup capacity scheduler XML and return queues for the user getYarnQueue() { grep $1 -B 1 /etc/hadoop/conf/capacity-scheduler.xml | awk -F’.’ ‘/name/{print $(NF-1)}’ } Works on Hortonworks HDP. Usage:...
Okay, so msck repair is not working and you saw something as below, 0: jdbc:hive2://hive_server:10000> msck repair table mytable; Error: Error while processing statement: FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask (state=08S01,code=1) It seems to appear because of higher...
Source: https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.6.1/bk_administration/content/distcp_between_ha_clusters.html DistCp Between HA Clusters To copy data between HA clusters, use the dfs.internal.nameservices property in the hdfs-site.xml file to explicitly specify the name services belonging to the local cluster, while continuing to use the dfs.nameservices property to specify all of the name services in...
Bash function to export Hive table data to local CSV file Usage: hive_export_csv <db.table> <output.csv> [queue] Recommendation: Add to .bash_profile hive_export_csv () { if [ -z “$2” ]; then echo “Bad arguments. Usage: ${FUNCNAME[0]} <db.table> <output.csv> [queue]” else uuid=$(uuidgen)...
Source: https://community.hortonworks.com/questions/112754/insert-overwrite-directory-beeline.html Error Error: Error while compiling statement: FAILED: HiveAccessControlException Permission denied: user [user] does not have [WRITE] privilege on [/tmp/*] (state=42000,code=40000) The above error appears, even though you’ve setup ranger policies, hdfs policies are set up. You’ve checked everything and...
Source: http://marcel.is/how-newline-can-ruin-your-hive/ If you do not fully understand how Hive/Impala stores your data, it might cost you badly. Symptom #1: Weird values in ingested Hive table You double-checked with select distinct(gender) from customers that the gender column in your source RDBMS really contains only values male, female and NULL....
Finding active namenode in a cluster Active namenode in a cluster # lookup active nn nn_list=`hdfs getconf -namenodes` echo Namenodes found: $nn_list active_node=‘’ #for nn in $( hdfs getconf -namenodes ); do for nn in $nn_list ; do echo...
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