How to set the JVM Garbage Collector logs to the stdout and not in /var/log/elasticsearch/gc.log

Elastic Stack Elasticsearch
1

Hello,

I would like to put an option in my docker-compose.yml (ES_JAVA_OPTS) to say at the JVM to write logs on the stdout but if I give the stdout path, it says that I don't have the rights ("permission denied") and I can't find any option to do that.. Is there a solution ?

I have seen that in /etc/elasticsearch/ there is a file jvm.options where the logs file path is specified :

-Xloggc:/var/log/elasticsearch/gc.log

Maybe is it possible to specify on the docker-compose to change this path to stdout or comment this line for let the default jvm parameter which is to write logs on the stdout ?

Please give me some ideas, I really don't know how to do :sweat_smile:

PS : when I change for example the name of the log file ("ES_JAVA_OPTS: -Xms1G -Xmx1G -Xloggc:/var/log/elasticsearch/gc_test.log" in docker-compose.yml), it works. It's just the stdout that doesn't work..

2

IIRC the default output is stdout, as long as the jvm options to print gc times are set, you can omit -Xloggc and then everything should be written to stdout.

3

Thanks for your answer,
Yes normally it's like that but ES change JVM default options so even if I don't specify -Xloggc in my docker-compose, it follows the ES jvm.options file which is in the docker container.. I would like to say in the docker-compose file to write JVM logs in the stdout and not to listen the jvm.options file