The advantage of having per-service log files is that it is very easy to analyze/monitor what went wrong in this particular service (proxy service, data service etc.) by looking at the service log. Enabling this feature will not terminate the wso2-ei.log file. This This file will contain the complete log with every log statement, including the service logs that you have configured to be logged into a different log file. In other words, the service log is an additional log file, which will contain a copy of the logs to that particular service.
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