Upgrading Timeline Server 1.0 to 1.5
| ![[Warning]](../common/images/admon/warning.png) | Warning | 
|---|---|
| Upgrading from ATS v1 to v1.5 may cause data stored in ATS v1.0 storage to be inaccessible. The upgrade process is not rolling: applications may lose previous data stored in ATS v1.0 during upgrade. | 
Before launching ATS v1.5, ensure your system is compliant with the following:
- yarn.timeline-service.entity-group-fs-store.active-dirand- yarn.timeline-service.entity-group-fs-store.done-dirmust exist on the cluster on HDFS. Active-dir should have permission 01777, owned by YARN, group admin-group. Done-dir should have permission 0700, owned by yarn, group admin-group.
- You must manually create - yarn.timeline-service.entity-group-fs-store.active-dirin HDFS before you start RM and ATS.
- The Tez cache plugin class must be in the timeline server’s classpath. 
- yarn.timeline-service.leveldb-timeline-store.pathmust be a path on the local filesystem and must be created with permissions 755. The owner must be the same user that timeline server is running as.
- To upgrade to ATS 1.5, configure the following: - <property> <name>yarn.timeline-service.version</name> <value>1.5</value> <description>Timeline service version we’re currently using.</description> </property> <property> <name>yarn.timeline-service.store-class</name> <value>org.apache.hadoop.yarn.server.timeline.EntityGroupFSTimelineStore</value> <description>Main storage class for YARN timeline server. </description> </property> <property> <name>yarn.timeline-service.entity-group-fs-store.active-dir</name> <value>/ats/active/</value> <description>DFS path to store active application’s timeline data</description> </property> <property> <name>yarn.timeline-service.entity-group-fs-store.done-dir</name> <value>/ats/done/</value> <description>DFS path to store done application’s timeline data</description> </property> 
- The following configuration exists in ATS v1.0, ensure it is pointing to the correct directory: - <property> <name>yarn.timeline-service.leveldb-timeline-store.path</name> <value><Data disk>/ats/leveldb/</value> <description>Local FS path to store the leveldbs that hold the application summary data</description> </property> 
- If you have Tez enabled, the tez-client must be installed on the ATS server. You must also perform this additional step: - <property> <name>yarn.timeline-service.entity-group-fs-store.group-id-plugin-classes</name> <value>org.apache.tez.dag.history.logging.ats.TimelineCachePluginImpl</value> <description>Plugins that can translate a timeline entity read request into a list of timeline cache ids, separated by commas. </description> </property>
- Configure the yarn.timeline-service.entity-group-fs-store.summary-store property: - <property> <name>yarn.timeline-service.entity-group-fs-store.summary-store</name> <description>Summary storage for ATS v1.5</description> <value>org.apache.hadoop.yarn.server.timeline.RollingLevelDBTimelineStore</value> </property>

