a34358f0_e_Hadoop_2_7_1___YARN_Commands__Description
[COMMAND_OPTIONS] -transitionToActive [–forceactive] [–forcemanual] [Description] 
Transitions the service into Active state. Try to make the target active without checking that there is no active node if the –forceactive option is used. This command can not be used if automatic failover is enabled. Though you can override this by –forcemanual option, you need caution.
Apache Hadoop 2.7.1 – YARN Commands