Flume Daemons

Flume Daemons are Flume Master and Flume Node

The Flume Master is the central management point and controls the data flows of the nodes. It is the single logical entity that holds global state data and controls the Flume node data flows and monitors Flume nodes.The nodes periodically contact the Master to transmit a heartbeat and to get their data flow configuration.Flume system is working, you must start a single Flume Master and some Flume nodes that interact with the Master.

The Master can be manually started by executing the following command:
$ flume master
After the Master is started, you can access it by pointing a web browser to http://localhost:35871/. This web page displays the status of all Flume nodes that have contacted the Master, and shows each node’s currently assigned configuration. When you start this up without Flume nodes running, the status and configuration tables will be empty.
The web page contains four tables the Node status table, the Node configuration table, the Physical/Logical Node mapping table, and a Command history table.

The Flume NodeTo start a Flume node, invoke the following command
$ flume node_nowatch

On the master, a node can be in one of several states

HELLO : A new node instance initially contacted the master.
IDLE : A node has completed its configuration or has no configuration.
CONFIGURING: A node has received a configuration and is activating the configuration.
ACTIVE: A node is actively pulling data from the source and pushing data into the sink.
LOST: A node has not contacted the master for an extended period of time (default is after 10x the expected heartbeat period 50s by default)
DECOMMISSIONED: A node has been purposely decommissioned from a master.
ERROR: A node has stopped in an error state.