The health test result for DATA_NODE_SCM_HEALTH has become bad.The roles process failed to start

[#1]

The health test result for DATA_NODE_SCM_HEALTH has become bad.The roles process failed to start

Suddenly one of the Datanode of my production cluster started showing dead with above error.

stopped and started the cloudera manager agent with command (service cloudera-scm-agent start/stop)  on the node but no go.

Datanode service failing with error on start so its remain dead.

Can anyone help me Please.

[#2]

The first thing to do would be to look at the role log for the datanode that's not starting up. That'll typically have a stacktrace that points to what's wrong.