YARN-7754. [Atsv2] Update document for running v1 and v2 TS. Contributed by Suma Shivaprasad.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/markdown/TimelineServiceV2.md

@@ -333,6 +333,18 @@ that it can write data to the Apache HBase cluster you are using, or set
 </property>
 ```
 
+To configure both Timeline Service 1.5 and v.2, add the following property
+
+ ```
+ <property>
+   <name>yarn.timeline-service.versions</name>
+   <value>1.5f,2.0f</value>
+ </property>
+```
+
+If the above is not configured, then it defaults to the version set in `yarn.timeline-service.version`
+
+
 #### Running Timeline Service v.2
 Restart the resource manager as well as the node managers to pick up the new configuration. The
 collectors start within the resource manager and the node managers in an embedded manner.