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While restarting cluster services I am getting an error at "Restart Atlas metadata Sever". Please help

-zn,--znode </ambari-solr> Zookeeper ZNode
java.util.concurrent.TimeoutException: Could not connect to ZooKeeper,, within 15000 ms
java.util.concurrent.TimeoutException: Could not connect to ZooKeeper,, within 15000 ms. Sleeping for 5 sec(s)
2019-09-18 19:59:41,658 - Execute[' JAVA_HOME=/usr/lib/java/jdk1.8.0_121/ /usr/lib/ambari-infra-solr-client/ --zookeeper-connect-string,, --znode /infra-solr --check-znode --retry 5 --interval 10'] {}

Command failed after 1 tries



@Former Member 

Atlas uses the hbase as backend database  datastore when its managed by Ambari. So, basically it uses two Hbase tables to store all its metadata.

  • 'atlas_titan' : stores all the metadata from various sources.
  • 'ATLAS_ENTITY_AUDIT_EVENTS': stores the audit information of the entities in Atlas you should ensure these 2 tables  exist in  hbase 

It would be a good idea to share  your atlas log /var/log/atlas/application.log

Connect to hbase

# su - hbase
$ hbase shell
hbase(main):001:0> list
6 row(s) in 2.8660 seconds

=> ["ATLAS_ENTITY_AUDIT_EVENTS", "PDFTable", "PDFTable:DOCID001", "atlas_titan", "jina", "testtable3"]

The important tables are highlighted in blue, these tables MUST exit for Atlas to fire up next check the entry in zookeeper


Check the zookeeper entry

Navigate to the  client or server

cd /usr/hdp/current/zookeeper-client/
$ ./bin/
[zk: localhost:2181(CONNECTED) 0] ls /hbase-unsecure/table
[ATLAS_ENTITY_AUDIT_EVENTS, hbase:meta, jina, atlas_titan, hbase:namespace, PDFTable:DOCID001, PDFTable, hbase:backup, hbase:acl, testtable3]

Check the ACL 
[zk: localhost:2181(CONNECTED) 1] getAcl /hbase-unsecure/table/atlas_titan

: cdrwa

It should have world permissions as shown above


If  Atlas doesn't  fire up, it could be a good last try to drop altogether with the  atlas related tables, connect to the HBase shell  and execute the below steps

Stop Atlas via Ambari.
From the hbase shell to disable hbase table, run this command.
disable 'atlas_titan'
While still in HBase shell, to drop Atlas hbase related tables, run this command.
drop 'atlas_titan'
exit HBase CLI

Start Atlas via Ambari the above tables should be recreated.





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