Log levels are set in Kong’s configuration. Following are the log levels in increasing order of their severity:
debug: It provides debug information about the plugin’s run loop and each individual plugin or other components. This should only be used during debugging, the
debug option, if left on for extended periods of time, can result in excess disk space consumption.
notice: Kong does not make a big difference between both these levels. Provides information about normal behavior most of which can be ignored.
warn: To log any abnormal behavior that doesn’t result in dropped transactions but requires further investigation,
warn level should be used.
error: Used for logging errors that result in a request being dropped (for example getting an HTTP 500 error). The rate of such logs need to be monitored.
crit: This level is used when Kong is working under critical conditions and not working properly thereby affecting several clients. Nginx also provides
emerg levels but currently Kong doesn’t make use of these levels making
crit the highest severity log level.
notice is the default and recommended log level. However if the logs turn out to be too chatty, they can be bumped up to a higher level like