How to change openshift-sdn loglevel in OpenShift 4.5+?

Environment

• Red Hat OpenShift Container Platform (RHOCP)
  • 4.5+
• Container Network Interface (CNI)
  • OpenShift SDN

Issue

• How to increase the log level of the OpenShift SDN in OpenShift 4?
• As an administrator to debug an issue increasing the loglevel of the sdn in required

Resolution

• This article is intended for OpenShift Container Platform 4.5+. To raise the sdn loglevel in OpenShift Container Platform 4.4 or earlier, please follow article 5311361.

• To raise the sdn loglevel in OpenShift Container Platform 3, visit this article.

• Create a ConfigMap named env-overrides in openshift-sdn namespace specifying the name(s) of the node(s) you want to set the debug loglevel on and/or _master in order to change the sdn-controller log level:

   kind: ConfigMap
   apiVersion: v1
   metadata:
     name: env-overrides
     namespace: openshift-sdn
   data:
     _master: |
       OPENSHIFT_SDN_LOG_LEVEL=5
     ip-10-0-135-96.us-east-2.compute.internal: |
       OPENSHIFT_SDN_LOG_LEVEL=5
     ip-10-0-101-42.us-east-2.compute.internal: |
       OPENSHIFT_SDN_LOG_LEVEL=5

• Restart the sdn and/or sdn-controller pods to pickup the new loglevel:

   oc delete pod -n openshift-sdn -l app=sdn --field-selector spec.nodeName=ip-10-0-135-96.us-east-2.compute.internal 
   oc delete pod -n openshift-sdn -l app=sdn --field-selector spec.nodeName=ip-10-0-101-42.us-east-2.compute.internal 
   oc delete pod -n openshift-sdn -l app=sdn-controller

• Note that restarting an openshift-sdn pod may cause a connectivity glitch on the node. In case any sensitive workload is running on the node it is recommended to drain it first and uncordon it afterwards.

Root Cause

• The default loglevel for openshift-sdn is 2
• The recommended loglevel if you need to debug the openshift-sdn is 5

Diagnostic Steps

Check if there is any custom log level by checking on the config map:

oc -n openshift-sdn get cm/env-overrides -o yaml

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