"failed to fetch KongPlugin: no KongPlugin or KongClusterPlugin was found" errors in the KIC logs

My Ingress rule or KongConsumer references a konghq.com/plugins annotation with a plugin name that does not exist, and Kong Ingress Controller is failing to apply the configuration as a result.

How can I find the affected resource and stop these errors?

Note: current versions of Kong Ingress Controller no longer log the string failed to fetch KongPlugin: no KongPlugin or KongClusterPlugin was found anywhere in the controller logs. Instead, this failure surfaces only as a Kubernetes Warning Event on the affected resource — check kubectl get events or kubectl describe on the relevant Ingress/KongConsumer for a Warning Event describing the missing KongPlugin/KongClusterPlugin, rather than grepping the controller logs.

The error suggests that you have created an Ingress rule or KongConsumer, and added a konghq.com/plugins annotation using a plugin name which does not already exist. This can be the case when the plugin is created in a different namespace than the Ingress rule or KongConsumer.

If you do not know which resource could be at fault because this is something that was created by a different team, you can try the following steps to find the relevant resource, and delete it:

1. Find all KongPlugins, and KongClusterPlugins in all workspaces:

kubectl get KongClusterPlugins --all-namespaces
kubectl get KongPlugins --all-namespaces

1. Check if you have any Ingress rules that reference a plugin that does not exist in either of the outputs above:

a) find all Kong Ingress rules in all workspaces:
kubectl get ing --all-namespaces

b) run the following for each Ingress rule found in a)
kubectl describe -n <relevantnamespace> ing <ingressname>|grep "konghq.com/plugins"

1. Check if you have a Consumer with a plugin configured that was not returned in step 1

1. Find all KongConsumers configured
kubectl get KongConsumer --all-namespaces

2. Find which plugins are configured for each consumer:
kubectl describe -n <relevantnamespace> KongConsumer <kongconsumerreturnedin1>|grep "konghq.com/plugins"

1. If you find a Kong Consumer or Ingress rule that has a non existent plugin configured, edit or delete the relevant Ingress rule as appropriate, and the log entries should stop