Elasticsearch 7.3 logging hierarchies and levels

[gdamico (Gian Piero D' Amico)]

Hi,

I'd like to get a greater detail on discovery process when a node starts. I found this: ES 7.3 Logging configuration

So, I think this is the best approach:
./bin/elasticsearch -E <name of logging hierarchy>=<level>

My problem: I can't find documentation about the valid hierarchies and levels. Where can I find it? What's the right hierarchy and level for my purpose?

Reading the log4j2.properties file I found some posible hierarchies, but I'd like to be sure.

Thanks in advance.

[DavidTurner]

The log levels are the standard Log4J levels (ERROR, WARN, INFO and so on). The logging hierarchy is tied closely to the package hierarchy in the source code. It can change quite substantially between versions as code moves around, so it's deliberate that there's not really any other documentation about it.

The discovery process in 7.3 is pretty much all under org.elasticsearch.discovery so you could try setting logger.org.elasticsearch.discovery to TRACE. As well as configuring a logger on the command line you can add logger.org.elasticsearch.discovery: TRACE to your elasticsearch.yml or even set it dynamically through the API:

PUT /_cluster/settings
{"persistent":{"logger.org.elasticsearch.discovery":"TRACE"}}

[gdamico (Gian Piero D' Amico)]

Thanks a lot for your reply!