Troubleshooting

Log Levels

The following log levels are used in Rancher:

Name Description

info

Logs informational messages. This is the default log level.

debug

Logs more detailed messages that can be used to debug.

trace

Logs very detailed messages on internal functions. This is very verbose and can contain sensitive information.

How to Configure a Log Level

Kubernetes Install

  • Configure debug log level

    $ KUBECONFIG=./kube_config_cluster.yml
    $ kubectl -n cattle-system get pods -l app=rancher --no-headers -o custom-columns=name:.metadata.name | while read rancherpod; do kubectl -n cattle-system exec $rancherpod -c rancher -- loglevel --set debug; done
    OK
    OK
    OK
    $ kubectl -n cattle-system logs -l app=rancher -c rancher
  • Configure info log level

    $ KUBECONFIG=./kube_config_cluster.yml
    $ kubectl -n cattle-system get pods -l app=rancher --no-headers -o custom-columns=name:.metadata.name | while read rancherpod; do kubectl -n cattle-system exec $rancherpod -c rancher -- loglevel --set info; done
    OK
    OK
    OK

Docker Install

  • Configure debug log level

    $ docker exec -ti <container_id> loglevel --set debug
    OK
    $ docker logs -f <container_id>
  • Configure info log level

    $ docker exec -ti <container_id> loglevel --set info
    OK

Rancher Machine Debug Logs

If you need to troubleshoot the creation of objects in your infrastructure provider of choice, rancher-machine debug logs might be helpful to you.

It’s possible to enable debug logs for rancher-machine by setting environment variables when launching Rancher.

The CATTLE_WHITELIST_ENVVARS environment variable allows users to whitelist specific environment variables to be passed down to rancher-machine during provisioning.

The MACHINE_DEBUG variable enables debug logs in rancher-machine.

Thus, by setting MACHINE_DEBUG=true and adding MACHINE_DEBUG to the default list of variables in CATTLE_WHITELIST_ENVVARS (e.g. CATTLE_WHITELIST_ENVVARS=HTTP_PROXY,HTTPS_PROXY,NO_PROXY,MACHINE_DEBUG) it is possible to enable debug logs in rancher-machine when provisioning RKE1, RKE2 and k3s clusters.

Just like the trace log level above, rancher-machine debug logs can contain sensitive information.

Cattle-cluster-agent Debug Logs

The cattle-cluster-agent log levels can be set when you initialize downstream clusters.

When you create a cluster under Cluster Configuration  Agent Environment Vars you can set variables to define the log level.

  • Trace-level logging: Set CATTLE_TRACE or RANCHER_TRACE to true

  • Debug-level logging: Set CATTLE_DEBUG or RANCHER_DEBUG to true

The cattle-cluster-agent debug logs may contain sensitive information.