MapR 5.0 Documentation : dump rolebalancerinfo

The maprcli dump rolebalancerinfo command enables you to monitor the replication role balancer and view information about active replication role switches. For best results, use the -json option when running dump rolebalancerinfo from the command line.

The replication role balancer is a tool that switches the replication roles of containers to ensure that every node has an equal share of master and replica containers (for name containers) and an equal share of master, intermediate, and tail containers (for data containers).

The replication role balancer changes the replication role of the containers in a cluster so that network bandwidth is spread evenly across all nodes during the replication process. A container's replication role determines how it is replicated to the other nodes in the cluster. For name containers (the volume's first container), replication occurs simultaneously from the master to all replica containers. For data containers, replication proceeds from the master to the intermediate container(s) until it reaches the tail containers. For more information, see Replication Role Balancer.


maprcli dump rolebalancerinfo
    [-cluster <cluster name>]




-cluster <cluster name>

The cluster on which to run the command. If this parameter is omitted, the command is run on the same cluster where it is issued. In multi-cluster contexts, you can use this parameter to specify a different cluster on which to run the command.


The maprcli dump rolebalancerinfo command returns information about active replication role switches.

# maprcli dump rolebalancerinfo -json
                      "containerid": 36659,
                      "Tail IP:Port":"",
                      "Updates blocked Since":"Wed May 23 05:48:15 PDT 2012"


Output fields




The unique ID number of the container.

Tail IP:Port

The IP address and port number of the tail container node.

Updates blocked Since

During a replication role switch, updates to that container are blocked.


maprcli dump rolebalancerinfo -json