minio/docs/debugging

MinIO Server Debugging Guide

HTTP Trace

HTTP tracing can be enabled by using mc admin trace command.

Example:

minio server /data

Default trace is succinct only to indicate the API operations being called and the HTTP response status.

mc admin trace myminio

To trace entire HTTP request

mc admin trace --verbose myminio

To trace entire HTTP request and also internode communication

mc admin trace --all --verbose myminio

Subnet Health

Subnet Health diagnostics help ensure that the underlying infrastructure that runs MinIO is configured correctly, and is functioning properly. This test is one-shot long running one, that is recommended to be run as soon as the cluster is first provisioned, and each time a failure scenario is encountered. Note that the test incurs majority of the available resources on the system. Care must be taken when using this to debug failure scenario, so as to prevent larger outages. Health tests can be triggered using mc admin subnet health command.

Example:

minio server /data

The command takes no flags

mc admin subnet health myminio

The output printed will be of the form

● Admin Info ... ✔ 
● CPU ... ✔ 
● Disk Hardware ... ✔ 
● Os Info ... ✔ 
● Mem Info ... ✔ 
● Process Info ... ✔ 
● Config ... ✔ 
● Drive ... ✔ 
● Net ... ✔ 
*********************************************************************************
                                   WARNING!!
     ** THIS FILE MAY CONTAIN SENSITIVE INFORMATION ABOUT YOUR ENVIRONMENT ** 
     ** PLEASE INSPECT CONTENTS BEFORE SHARING IT ON ANY PUBLIC FORUM **
*********************************************************************************
mc: Health data saved to dc-11-health_20200321053323.json.gz

The gzipped output contains debugging information for your system