= Partition reassignment use cases =

= Adding broker =
Suppose brokers 0,1 are running and broker 2 was just started.
User wants to rebalance load of 0,1 between 0,1,2 brokers.

To archive that:
1. User generates reassignment configuration by running:
--rebalance --topics-to-move-json-file topics.json --broker-list 0,1,2 --zookeeper zk:2181
2. User copies proposed reassignment configuration to reassignment.json file
3. User executes reassignment by running:
--execute --reassignment-json-file reassignment.json --zookeeper zk:2181
4. User verifies status of reassignment by running:
--verify --reassignment-json-file reassignment.json --zookeeper zk:2181

= Removing broker =
Suppose brokers 0,1,2 are running.
User wants to decommission broker 2.

To archive that user runs:
--decommission-broker 2 --zookeeper zk:2181

= Replacing broker =
Suppose brokers 0,1,2 are running.
User wants to replace broker 2 with just started broker 3.

To archive that:
1. User generates reassignment configuration by running:
--rebalance --topics-to-move-json-file topics.json --broker-list 0,1,3 --zookeeper zk:2181
-- rest items are the same as for adding broker --

= Custom reassignment =
Suppose brokers 0,1 are running. User wants customize replica assignment.

To archive that:
1. User generates reassignment configuration by running:
--rebalance --topics-to-move-json-file topics.json --broker-list 0,1 --zookeeper zk:2181
2. User copies proposed reassignment configuration to reassignment.json file and customizes assignment
-- rest items are the same as for adding broker --