Hi,
Sure, we've all been there. Sadly this is just a general message about Logstash pipeline failing to start. After this log you might find reason or some kind of tip where the error might be. You can grep for Expected, here's an example:
[ERROR][logstash.agent ] Failed to execute action {:action=>LogStash::PipelineAction::Create/pipeline_id:generator, :exception=>"LogStash::ConfigurationError", :message=>"Expected one of [ \\t\\r\\n], \"#\", \"=>\" at line 5, column 26 (byte 132) after input {\n exec {\n command => 'sh -c \"/usr/share/logstash/data-generator.sh -logs\"'\n interval => 300\n\tthis_should_not_be_here", :backtrace=>["/usr/share/logstash/logstash-core/lib/logstash/compiler.rb:32:in `compile_imperative'", "org/logstash/execution/AbstractPipelineExt.java:184:in `initialize'", "org/logstash/execution/JavaBasePipelineExt.java:69:in `initialize'", "/usr/share/logstash/logstash-core/lib/logstash/java_pipeline.rb:47:in `initialize'", "/usr/share/logstash/logstash-core/lib/logstash/pipeline_action/create.rb:52:in `execute'", "/usr/share/logstash/logstash-core/lib/logstash/agent.rb:389:in `block in converge_state'"]}
[2023-04-18T13:44:48,403][INFO ][org.reflections.Reflections] Reflections took 62 ms to scan 1 urls, producing 23 keys and 47 values
You can see that I've added this_should_not_be_here string to my config, which resulted in error. Still - logstash pointed general location.
If there is nothing, I'd suggest looking at /etc/logstash/pipelines.yml file and check if there are no typos.