BTW to me it is not clear if you want to Drop Events... or Remove Fields...
Ok... can you share what you tried?
Can you share your config?
For most the cloud fields you can turn off the add metadata processor.
Not sure Which ECS fields you are referring to?
Some of the fields (agent and host I believe) are added AFTER the integration processing but you can certainly drop them in an ingest pipeline.... in fact you can do that with any / all the fields and often users find that to be an easy way to centralized removing fields.
There is documentation on how to do that here and here but instead of adding fields you can remove them and
In short Remove Processor
In Kibana Dev Tools
PUT /_ingest/pipeline/logs-kubernetes.container_logs@custom
{
"processors": [
{
"remove": {
"field": ["user_agent", "URL"] <<< Add Fields Here
}
}
]
}
If you want actually to Drop Whole Events...
You can do that with the processors at the Agent Level (again you would need to show us what you tried otherwise we are just guessing)
Or use Drop Event in the ingest Pipeline