To collect data from particular indices, configure the xpack.monitoring.collection.indices setting in elasticsearch.yml. You can specify multiple indices as a comma-separated list or use an index pattern to match multiple indices:

xpack.monitoring.collection.indices: logstash-*, index1, test2

You can prepend + or - to explicitly include or exclude index names or patterns. For example, to include all indices that start with test except test3, you could specify +test*,-test3.