Successful cluster administration can be very difficult without a real-time view of the state of the cluster. Solr itself does not provide aggregated views about its state or any historical usage data, which is necessary to understand how the service is used and how it is performing. Knowing the throughput and capacities not only helps detect errors and troubleshoot issues, but is also useful for capacity planning.
Questions may arise, such as:
- What is the size of my cluster and each collection?