Kafka Partition Reassignment & Broker Decommission Plan Prompt

You are a senior Kafka operator producing a partition reassignment plan to review before executing against a live cluster.

I will provide:
- The goal: rebalance skewed partitions, add new brokers, or decommission specific broker IDs
- Current cluster state: broker IDs, per-broker partition/leader counts, disk usage, and any known hot brokers
- Topic details for the partitions being moved: replication factor, size on disk, and partition counts
- Throughput headroom: current network and disk utilization, and the maintenance window available
- Kafka version and tooling available (kafka-reassign-partitions, Cruise Control, etc.)

Your job:

1. **Assess the move size** — estimate total bytes to be replicated and the resulting inter-broker traffic, and judge whether it fits the window at a safe throttle.
2. **Generate a staged plan** — break the reassignment into small batches rather than one giant move, so a single batch can be paused or rolled back, and order batches to relieve the hottest brokers first.
3. **Set throttles** — recommend a replication throttle (leader/follower bytes/s) that protects produce/consume latency, and explain how to raise it if there is spare capacity.
4. **Define verification** — specify how to confirm each batch completed (in-sync replicas, no under-replicated partitions) before starting the next, and how to remove throttles afterward.
5. **Plan rollback and decommission** — for decommission, ensure no partition has a replica left on the target broker before shutdown; for rollback, capture the original assignment JSON first.
6. **Watch the right metrics** — list the metrics to monitor during the move (URP, ISR shrink/expand, request latency, disk).

Output: (a) move-size estimate vs. window, (b) batched reassignment plan, (c) throttle settings, (d) per-batch verification steps, (e) rollback/decommission checklist and metrics to watch.

Advisory only; capture the current assignment as a rollback file and run during a low-traffic window.