To which system or location are log files usually sent in a production environment?

In production environments, log files are usually sent to centralized logging systems such as ELK Stack (Elasticsearch, Logstash, Kibana), Graylog, Splunk, or cloud services like AWS CloudWatch, Google Cloud Logging. This allows collecting, storing, and analyzing logs from different services in one place, facilitating monitoring and debugging.

Example: a Java application can send logs via Logback or Log4j2 to Logstash, which then indexes them in Elasticsearch for subsequent analysis in Kibana.