Cluster Node Properties

Configure these properties for cluster nodes.


Property	Description
`nifi.cluster.is.node`	Set this to `true` if the instance is a node in a cluster. The default value is `false`.
`nifi.cluster.node.address`	The fully qualified address of the node. It is blank by default.
`nifi.cluster.node.protocol.port`	The node's protocol port. It is blank by default.
`nifi.cluster.node.protocol.max.threads`	The maximum number of threads that should be used to communicate with other nodes in the cluster. This property defaults to `50`.
`nifi.cluster.node.event.history.size`	When the state of a node in the cluster is changed, an event is generated and can be viewed in the Cluster page. This value indicates how many events to keep in memory for each node. The default value is `25`.
`nifi.cluster.node.connection.timeout`	When connecting to another node in the cluster, specifies how long this node should wait before considering the connection a failure. The default value is `5 secs`.
`nifi.cluster.node.read.timeout`	When communicating with another node in the cluster, specifies how long this node should wait to receive information from the remote node before considering the communication with the node a failure. The default value is `5 secs`.
`nifi.cluster.node.max.concurrent.requests`	The maximum number of outstanding web requests that can be replicated to nodes in the cluster. If this number of requests is exceeded, the embedded Jetty server will return a "409: Conflict" response. This property defaults to `100`.
`nifi.cluster.firewall.file`	The location of the node firewall file. This is a file that may be used to list all the nodes that are allowed to connect to the cluster. It provides an additional layer of security. This value is blank by default, meaning that no firewall file is to be used. See Cluster Firewall Configuration for file format details.
`nifi.cluster.flow.election.max.wait.time`	Specifies the amount of time to wait before electing a Flow as the "correct" Flow. If the number of Nodes that have voted is equal to the number specified by the `nifi.cluster.flow.election.max.candidates` property, the cluster will not wait this long. The default value is `5 mins`. Note that the time starts as soon as the first vote is cast.
`nifi.cluster.flow.election.max.candidates`	Specifies the number of Nodes required in the cluster to cause early election of Flows. This allows the Nodes in the cluster to avoid having to wait a long time before starting processing if we reach at least this number of nodes in the cluster.
`nifi.cluster.load.balance.port`	Specifies the port to listen on for incoming connections for load balancing data across the cluster. The default value is `6342`.
`nifi.cluster.load.balance.host`	Specifies the hostname to listen on for incoming connections for load balancing data across the cluster. If not specified, will default to the value used by the `nifi.cluster.node.address` property. The value set here does not have to be a hostname/IP address that is addressable outside of the cluster. However, all nodes within the cluster must be able to connect to the node using this hostname/IP address.
`nifi.cluster.load.balance.connections.per.node`	The maximum number of connections to create between this node and each other node in the cluster. For example, if there are 5 nodes in the cluster and this value is set to 4, there will be up to 20 socket connections established for load-balancing purposes (5 x 4 = 20). The default value is `1`.
`nifi.cluster.load.balance.max.thread.count`	The maximum number of threads to use for transferring data from this node to other nodes in the cluster. While a given thread can only write to a single socket at a time, a single thread is capable of servicing multiple connections simultaneously because a given connection may not be available for reading/writing at any given time. The default value is `8`-i.e., up to 8 threads will be responsible for transferring data to other nodes, regardless of how many nodes are in the cluster. NOTE: Increasing this value will allow additional threads to be used for communicating with other nodes in the cluster and writing the data to the Content and FlowFile Repositories. However, if this property is set to a value greater than the number of nodes in the cluster multiplied by the number of connections per node (`nifi.cluster.load.balance.connections.per.node`), then no further benefit will be gained and resources will be wasted.
`nifi.cluster.load.balance.comms.timeout`	When communicating with another node, if this amount of time elapses without making any progress when reading from or writing to a socket, then a TimeoutException will be thrown. This will then result in the data either being retried or sent to another node in the cluster, depending on the configured Load Balancing Strategy. The default value is `30 sec`.