Logsidecar-injector

Logsidecar-injector is a Kubernetes mutating webhook server that adds a sidecar to your pod. This sidecar is just to forward logs from files on volumes to stdout.

Install

To quickly install the logsidecar injector inside a cluster, just run the following command:

kubectl apply -f https://raw.githubusercontent.com/kubesphere/logsidecar-injector/master/config/bundle.yaml

Note: it is default to install into the namespace kubesphere-logging-system

Usage

Suppose you want to inject the log sidecar into your workloads in the namespace default:

• Firstly add a label to the namespace:

  kubectl label ns default logging.kubesphere.io/logsidecar-injection=enabled

• Then add an annotation to pod template of your workload:

  spec:
    template:
      metadata:
        annotations:
          logging.kubesphere.io/logsidecar-config: 'VALUE'

  Note: the VALUE is a json string which has format as follows:

  {
      "containerLogConfigs": {
          "$containername": {
              "$volumename": [
                  "$relativepath"
              ]
          }
      }
  }

  relativepath is relative path to mountpath within container containername at which volume volumename was mounted.

• Optionally customize your configuration of filebeat in sidecar container:
  Add logging.kubesphere.io/logsidecar-filebeat-config-jsonpatch annotation to pod template of your workload. The value of this annotation is a jsonpatch string. Logsidecar-injector will generate a new configuration based on default filebeat configuration and this patch, then apply it to the injected sidecar container for your specified workload pod. Here is an example:

  spec:
    template:
      metadata:
        annotations:
          logging.kubesphere.io/logsidecar-filebeat-config-jsonpatch: '[{"op":"replace","path":"/filebeat.inputs/0/tail_file","value":true}]'